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TV & Video Hifi Computers What’s New! 


E xclusive to Dick Smith 
Electronics, these popular 
Velleman kits are produced and 
assembled in Belgium, and all come 
with a re-usable plastic container, 
pre-screened and pre-drilled PCBs 
and all components stripped in order 
of assembly. 

Parking radar 

No more parking problems with this 
kit emitting ultrasonic soundwaves to 
‘measure’ the distance between 
your car and other obstacles. A 
signal is generated when the pre¬ 
set distance is crossed. 

Supply voltage: 10-15V DC/16mA. 

Kojak siren 

Create or imitate sirens of all 
kinds by adjusting three trimmers. 
Powerful sound with an additional 
2W amplifier on the PCB. Power 
supply: 8-14V DC. 

Headlight indicator 

Set this headlight indicator either 
U to indicate the headlights should 
( be switched off after turning off 
the ignition, or to indicate that 
the headlights should be switched 

. on once the engine is on. Only 

(5 " B D Dg'Ol three wires needed to hook up. 

Supply voltage: 12V DC. 

K 1304 

24 ! 

K 1300 

Sound generator 

With one output for direct 

Screen wiper robot 

Select up to three different time 
intervals (2-10-15 seconds) for the 
windscreen wipers of your car. Manual 
includes installation instructions for 
most cars. Relays on PCB. 


a mixer panel or amplifier, generate 

$ 26 91 

■ l 

V ' 

i sound effects like phaser and 

i and explosions. 

[Supply voltage: 8-10V DC/100mA, 
IW speaker output. 

K 1301 


direct link 



PHONE: 1300 366 644 (Local Call Charge) FAX: (02) 9395 1155 

MAIL: DICK SMITH ELECTRONICS, Direct Link Reply Paid 160. 

PO Box 321, North Ryde NSW 21 13 (No Samp Required) 

Please add postage (up to 5kg) to your order, as follows: 

• $4.00 Up To $50 • $7.50 $51 Up To $100 • $9.00 $101 Up To $500 • $11.00 over $500 
(quote available for air/road freight or if over 5kg) email: (enquiries only) 
•Major Credit Cards Accepted. • Gift Vouchers Available 

LED control of set fluid level: low, 
middle, high. Controller: relay 
automatically switches a pump to keep 
fluid level between low and high marks. 
If sensor detects a level too high or low 
the relay activates a bell or the alarm 
device. (Not included) 

K 1307 

For further information, orders or the 
location of your nearest store call: 

1300 366 644 (Local Call Charge) 
Or Fax: (02) 9395 1155 

B 3443 IFC 

Australia’s largest selling electronics magazine — Established in 1922 

September 1998 Volume 60, No. 9 

World of Electronics 

6 What’s New Improved digital cameras from Canon and Olympus 
10 The Challis Report Pioneer’s PDP-V401E 40”plasma flat screen 

14 Quality Rising, Prices Still Falling The latest digital cameras... 

20 Olympus Camedia C-1400L Zoom lens, SLR viewfinder — wow! 

24 Moving People Safely with Electronics - 1 Car safety technology 

62 Moffat’s Madhouse Grrrrid-Lock: Can electronics help? 

70 Vintage Radio Two valve sets — 1927 to the pre-octal era 
74 Computer Clinic Creating your own Windows program, with the CGI 

Projects and Technical 

34 Serviceman The amp that was very nearly an expensive boat anchor! 
42 Circuit & Design Ideas Universal IR controller for a PC; more... 

44 ‘Front End’ for PC Audio Recording Use it to make your own CDs 

50 $10 Wonders 15 — A ‘designer’ door alert 

56 Intelligent Baby Alarm Using the Basic Stamp microcontroller 

Columns and Comments 

4 Letters to the Editor DVD players and regions; engine cutouts again 

5 Editorial Viewpoint From playtoy to invaluable tool, in a few years! 

30 Forum Atmospheric research isn’t new; and TBC or video synchroniser? 
67 Information Centre MOVs, battery ratings and the Y2K issue... 


33 Book Reviews 

76 EA History, Crossword 

82 EA Subscriptions Offer 

83 Marketplace 

97 Webwatch 

98 Directory of Suppliers 
98 Advertisers Index 

98 Notes & Errata 

Impressive performance 

The new Olympus C-1400L has a 3X 
zoom, TTL viewfinder & higher-res 
images. (See our feature on p. 14 too) 

Big screen, huge impact... 

Pioneer s new plasma display has 
great impact, as does its price (gulp!) 

Audio recording ‘front end’ 

On the cover uciir 

Volvo s S80, just 
released, features 
a wealth of safety 
features — many 
of them based on 
electronics. As 
well as the airbags 
used in previous 
models, there’s a new Inflatable Curtain 
that deploys in 25ms, to provide more 
side impact protection. See our feature 
story on car safety starting on page 24. 
(Photo courtesy Volvo Australia) 

Like to try digital recording, using 
your PC? This new project can help... 

Professional Electronics 

78 News Highlights Bluegum buys Alcatel’s Liverpool manufacturing plant 
84 Solid State Update CCD and CIS signal processor from Analog Devices 
86 New Products Handheld tester finds comm cable faults; tiny switcher 
88 Silicon Valley Newsletter Will Apple bounce back with the new iMac? 

90 Designer’s Guide to Charging Li-Ion Batteries - 2 Charger circuits 

93 Spotlight on Software Leprechaun’s Macro Virus Buster 

94 Computer News & New Products Handheld Fast Ethernet link tester 

ELECTRONICS Australia, September 1998 



Jamieson Rowe, B.A., B.Sc., SMIREE, VK2ZLO 


Rob Evans, CET (RMIT) 


Graham Cattley 


Witold Budzynski, B.Sc. 


Louis Challis 

Roger Johnson, VK5ZKP 

Jim Lawler, MTETIA 

Jon Loughron, Assoc. Dip. Elect. 

Tom Moffat, VK7TM 

Peter Phillips, B.Ed., Dip Ed., ECC 


Ana Marie Zamora; phone (02) 9353 0620 


Jean-Baptiste Cattley 


Jon Lesjak; phone (02) 9353 0734 


Pamela Sceats; phone (02) 9353 0629 


Brett Baker 


Michael Prior 


Christine Whiston 


Geoff Baggett 


PO Box 199, Alexandria 2015. 

180 Bourke Road, Alexandria 2015. 

Phone (02) 9353 0620; fax (02) 9353 0613 
Web site: 
Computer Bulletin Board: (02) 9353 0627 

Subscriptions Enquiries: 

phone (02) 9353 9992; fax (02) 9353 0967. 


MELBOURNE: Kayren Browne 

Level 8. 492 St Kilda Road, Melbourne 3004. 

Phone (03) 9864 1222; fax (03) 9864 1211. 

BRISBANE: Graham Smith 

26 Chermside Street, Newstead 4006. 

Phone (07) 3854 1119; fax (07) 3252 3692. 
ADELAIDE: Sue Bowshall 
98 Jervois Street, Torrensville, 5031. 

Phone (08) 8352 7937; fax (08) 8352 6033. 
PERTH: JWP Media Specialists 
64 Francis Street, Karrinyup 6018. 

Phone (08) 9446 2792; fax (08) 9446 2740. 

Magazines, a division of Eastern Suburbs 
Newspapers Partnership, which is owned by 
General Newspapers Pty Ltd. 

A.C.N.000 117 322, 

Double Bay Newspapers Pty Ltd. 

A.C.N.000 237 598. and 
Brehmer Fairfax Pty Ltd. 

A.C.N.008 629 767, 

180 Bourke Road, Alexandria, NSW 2015. 
Copyright © 1998 by FPC Magazines, Sydney. All 
rights reserved. No part of this publication may be 
reproduced in any way without written permission 
from the General Manager or Managing Editor. 
Printed by Macquarie Print, 51 - 59 Wheelers 
Lane, Dubbo 2830. Phone (02) 68 843 444. 
Distributed by Newsagents Direct Distribution 
Pty Ltd, 150 Bourke Rd, Alexandria 2015; 
phone (02) 9353 9911. 

ISSN 1328-6218 

* Recommended & maximum 
Australian retail price. 

Member of the Audit 
Bureau of Circulations 



Letters fo 

Stick with leeches? 

Being but a humble technician, I’ve 
always entrusted my health to my GP. 
However as a result of reading your 
recent Forum series I now realise that my 
erythrocites are being invaded by alien 

Since your research has obviously 
provided you with considerable expertise 
on the topic, I am really desperate for 
your advice. Do you reckon that I ought 
purchase Dr Beck’s Blood Cleaner, or 
should I just stick with the leeches? ;-( 

John Harvey, Clermont Old. 

Engine cutout legality 

A letter in the July edition refers to an 
engine cutout caused by a broken fan 
belt as being illegal. 

I don’t think so. LPG convertors will 
freeze up in seconds (stopping fuel 
supply) if the fan belt breaks — and they 
are legal. 

Andrew Caris (via e-mail) 

Idea not new 

Graham Pratt’s idea about using resist 
ink to print circuit boards directly from a 
CAD program isn’t new (EA July 98). 

About 10 years ago I was making one- 
off boards for research using resist ink in 
a pen plotter and plotting directly onto 
the copper surface. The resist ink 
happens to be the same as the ink used 
by farmers to write numbers on the ear- 
tags of cattle, and you can buy it cheaply 
in 200ml bottles (which makes more 
circuit boards than you will ever need). 

The trouble with inkjet printers may be 
that they are much more particular about 
the flow qualities of the ink than a plotter 

Chris Henderson (via e-mail) 

Aristocrat radio 

I am rejuvenating a seven valve Aristocrat 
ESM radio (1930 vintage), and wonder if 
any of your readers have a circuit dia¬ 
gram or any servicing details (IFT fre¬ 
quencies, etc). 

The circuit is a superhet with a triple 
gang tuning capacitor linking a 6K7G RF 
stage in front of a 6A8G heptode 
frequency changer, followed by an 
(unreadable) IF stage, a 6B6G 
demodulator and 6V6G output with a 
5Y3 HT rectifier and 6G5 magic eye 

the Editor 

tuning indicator. Apart from the RF stage, 
the circuit appears broadly similar to that 
of the RCNZ radio in your magazine issue 
of September 1994. 

The set is powered by a (nominally) 
380-0-380V transformer with full wave 
rectification. 320V DC on the cathode of 
the 5Y3 rectifier falls to 140V after 
smoothing by the 2800£2 field coil of the 
speaker (indicating a reasonable 
consumption of about 60mA). This 
voltage is well below the 250V 
anticipated for the valves, but after the 
mandatory replacement of paper 
capacitors, the radio is surprisingly 
receiving speech and music without 

For your information, I’m a chemical 
engineer who cut his teeth on home-built 
TV’s using war surplus ex-RAF 1355 
receivers and VCR517 tubes in Britain in 
the early 1950s. The heating from the 
multitude of VR65’s served a dual 
purpose of keeping the room warm in 
winter! The inevitable conversion to 
transistors and ICs through building 
circuits in Electronics Australia over 25 
years has not diminished my interest in 
your articles on thermionic valves. 

J.M. Costello, Woronora NSW. 

DVD players 

Having read your review of the Philips 
DVD840, I thought I should write. I have 
been following the development of DVD 
since the beginning, always knowing that 
I wanted to buy a player. However, that 
was put on hold when I read that there 
would be zones to stop individuals 
importing, pirating, etc movie titles. 

Thankfully the Internet came to the 
rescue, with many sites describing how to 
defeat the zone coding in each brand and 
model of player. Armed with this 
information, and on a recent holiday in 
Malaysia, I bought a DVD player (for 
considerably less than in Australia — 
$600 US!). Imagine my amazement 
when told that my purchase had been 
already modified by the distributor in 
Malaysia so as to defeat zoning! To prove 
it, the vendor played me a disc stamped 
Zone 1, and another Zone 4. 

Recently, in an American magazine, it 
was proudly reported that sales of DVD 
players and software had overtaken VHS 
for the first time. With the advent of the 

Editorial Viewpoint 

‘Net, and shopping on-line, it’s not hard 
to understand why. 

Frustrated Australian consumers would 
be very tempted to buy a DVD player 
coded for Zone 1 (US and Canada), 
purely because it guarantees the 
individual access to more than 2500 
movie titles, and interactive games, 
available now. By contrast, I have been 
able to source fewer than 20 titles in 
Australia, with explanations from retailers 
that “the Copyright holder won’t allow 
that title into Australia”. Stargate and The 
Fifth Element are two such examples. 

Why? What do the copyright holders 
have to gain? Are they waiting for people 
to stampede the distributors looking for 
titles? A typical ‘chicken and egg’ 
situation, I think! They won’t release the 
titles until everyone has a player, but 
people won’t buy the players until there’s 
a good range of movies! In the age of the 
Internet, the Australian distributors of 
movies are being foolishly parochial. 

It is my humble opinion that DVD will 
fail in Australia, like DCC and MiniDisc. 
There WILL, however, be booming import 
activity, with many people opting to buy 
with their Internet browsers and credit 
cards. Surf to, 
and you’ll see why. The prices, and the 

Mark Borchers, Melbourne Vic. 

It may have worked 

Regarding the circuit shown in Fig.4 of 
July’s Vintage Radio, on page 50, surely 
the circuit will vtfork as the A- supply for 
filaments is not earthed, whereas the 
bottom of the RF coil IS earthed. 
Therefore the secondary of coil 5 is not 
shorted out. It will pump the filament up 
and down with the audio, whilst holding 
the grid at earth potential. 

It looks as if all filaments and B supply 
follow audio with respect to earth and the 
bottom of the RF coil, if you get my 

Weird, but it probably did work. 

Peter Ball (via e-mail) ❖ 

Letters published in this column express the opinions of 
the correspondents concerned, and do not necessarily 
reflect the opinions or policies of the staff or publisher of 
Electronics Australia. We welcome contributions to this 
column, but reserve the right to edit letters which are very 
long or potentially defamatory. 


From playtoy 
to invaluable 
in only a 
few years... 


he other day I found myself doing two superficially 
quite different things, in short order. One was using the 
World Wide Web or ‘WWW’ to get some information on 
a new medication that my wife had been prescribed, by a 
doctor too busy to answer her questions about it; the other 
was looking up an article in an old issue of the magazine 
itself. I was really impressed by the contrast between the 
two actions, and in particular what they revealed about the 
dramatic developments that have taken place in computers 
and information technology, in the last few years. 

It turned out that I was able to get some really good infor¬ 
mation on the medication concerned, 
from both the manufacturer’s web site 
and also from a consumer information site 
in the US. There was a full pharmacologi¬ 
cal rundown, information on how it’s 
believed to work, indications and contra¬ 
indications, recommended dosage levels 
and so on — plus a great deal of informa¬ 
tion on the research and testing that had 
gone on in various countries, before it had 
been approved by bodies like the 
American FDA. 

All of this information was available 
freely and in very short order, simply by 
making use of the tremendous resources 
provided by today’s Internet/WWW, its 
search engines and the databases available at web sites around the world. Just as 
you can also get excellent up-to-date information on almost any electronic device or 
component — often faster than looking up a data book. 

We tend to take these resources for granted now, don’t we? But when I was look¬ 
ing up something in the May 1997 issue, I noticed a couple of articles which remind¬ 
ed me just how far we’ve come in the last 21-odd years... 

Back then, we were building and struggling to understand the first generation of DIY 
microcomputers and ‘evaluation kits’, like the Mini Scamp and the Motorola 6800 kit. 
Even the first true 8-bit personal computers like the Apple II and the Tandy TRS-80 
were yet to be released, and many people in electronics thought we were foolish to 
even bother with ‘those little toy computers’ — they’d never be of much use! 

Little did we even dream of the kind of computing resources that many of us would 
have on our desktops today — Pentium and Pentium II powered beasts screaming 
along at 200MHz-plus speeds, with tens of megs of RAM, multi-gigabyte hard disks 
and high-speed modems, and running all kinds of powerful software. 

The same kind of developments have taken place with the internet, of course. 
Initially it was of interest only to scientists, academics and the military, to link up their 
big computers and networks. Then it began to be used for international e-mail, and 
other people started to get involved. Then the WWW appeared and began to blossom, 
and both the resources and users began to grow exponentially. 

Only three or four years ago, I confess that I myself tended to see the WWW as a 
huge electronic information ‘rubbish dump’, with a small amount of fact buried almost 
irretrievably in an enormous amount of uninformed opinion. As with DIY computers 20 
years ago, it seemed little more than a hi-tech time waster. But that’s all changed, 
thanks to the development of primary and meta ‘search engines’, and the enormous 
amount of genuine information that’s been made available. 

Things can move pretty quickly from the ‘toy’ stage to the ‘invaluable resource tool’ 
stage, can’t they? 

Jim Rowe 

ELECTRONICS Australia, September 1998 5 


in the ever-changing world of electronics 

Hi-res multimedia video projector 

Hitachi’s new CP-X950 is a true XGA resolution (1024 x 768) LCD 
panel based multimedia projector, claimed to be ideal for business and 
educational applications where high resolution is essential, such as in 
the display of fine CAD drawings or high resolution photo images. 

A three-panel LCD projector, it uses a Hitachi ‘Polarisation 
Converter’ to provides 550 ANSI lumens of light output — one of the 
brightest displays in its price class. And despite having a weight of 
only 9kg, it’s enclosed in a solid frame that needs no extra mounting 
brackets if ceiling mounting is desired. The rugged frame also protects 
the unit from transit damage and distortion. For further protection the 
zoom lens is fully mounted within the projector case and a built-in lens 
shutter protects the lens from accidental scratching or worse. 

The CP-X950 incorporates a Multi-Scan Panel that accepts two 
PC inputs, two S-Video and two composite video inputs. These are 
all automatically detected and the display resolution adjusted 

Sharp Handheld PC features Windows CE 2.0 

Sharp Corporation says its new pocket-sized Handheld PC with 
Windows CE 2.0 is capable of giving a complete multimedia pre¬ 
sentation. It features either a mono or a full colour screen, reflecting 
Sharp’s dominance in LCD screens — they claim to produce 60% of 
those currently sold worldwide. Surprisingly there’s also a VGA 
output, which allows the HPC to facilitate big-screen presentations. 

Other features of the HC4100 A include an IrDA infra-red port for wire¬ 
less exchange of data, SMB of memory and an easy-touch keyboard. An 
optional extra is a digital camera which slips into the unit’s PC card slot. 

RRP for the HC4100A with mono colour screen is $999, or with 
colour screen $1499. The optional digital camera is $599. For more 
information circle 140 on the reader service card or contact Sharp 
Corporation, 1 Huntingwood Drive, Huntingwood 2148. 

depending on the signal frequency from compressed S-VGA, true 
XGA and expanded VGA and S-VGA. 

Available from authorised Hitachi dealers Australia wide, the 
CP-X950 has an RRP of $13,499 including tax. For more informa¬ 
tion circle 145 on the reader service card or contact Hitachi 
Australia, 13-15 Lyonpark Road, North Ryde 2113. 

New palm-size PC 
has voice control 

Casio’s new Cassiopeia E-10 is 
claimed as one of the first palm size 
PCs powered by Microsoft Windows 
CE 2.0 to go on sale in Australia, and 
is claimed to deliver instant access to 
vital business and personal informa¬ 
tion whenever and wherever it is need¬ 
ed — plus voice control. 

Compact, lightweight and easy 
to use, it offers users ‘seamless 
desktop synchronisation’, infrared 
(IR) capabilities, 4MB of RAM 
and 8MB of ROM memory, 
expandability via its CompactFlash 
port and a large easy to read 240 x 
320 dot LCD screen. Backlighting 

provides easy viewing of data even in 
the dark, while a pop-up handwriting 
or keyboard panel and taskbar allows 
up to 30% more viewable screen. 

Applications can be launched either 
by pressing one of the four application 
buttons, or by voice command using 
bundled software. Data input and other 
operations are performed by using a sty¬ 
lus or pressing the on-screen keyboard. 
Side positioned scrolling, enter and 
escape buttons make it possible to oper¬ 
ate the E-10 with one hand. 

The Cassiopeia E-10 has an RRP of 
$699 and is available at leading 
resellers and retail stores. For more 
information circle 149 on the reader 
service card or contact Mobex, 72-74 
Gibbes Street, Chatswood 2067. 


ELECTRONICS Australia, September 1998 


High-end CDP/tuner for mobile hifi 

Not intended for the average car audio lis¬ 
tener, Pioneer’s new DEX-P88R compo¬ 
nent tuner is designed for the audio enthusi¬ 
ast who is not satisfied with a factory-con- 
figured system. It is claimed to employ the 
very latest in car audio features, including 
‘Sound Q’ — a combination of four tech¬ 
nologies: Hi-Bit Digital Processing, Legato 
Link Conversion, Hi-Volt Preamp Outputs, 
and Zero-Bit Muting. 

Hi-Bit Digital Processing apparently com¬ 
bines the best features of both single-bit and 20- 
bit conversion. It uses a single-bit DAC, but 
first converts each 16-bit digital ‘word’ into a 
new 20-bit word, for enhanced detail. Pioneer’s 
Legato Link circuit then restores the upper har¬ 

monics of the music, normally lost during the 
digital recording process. 

The preamp outputs have been 
enhanced by the newly reworked Hi-Volt 
(4V) design to provide a clean¬ 
er and more powerful signal to 
the system’s amplifiers. 

The DEX-P88R will connect 
to a multiplay CD changer that 
can be mounted out of sight in 
the boot, under a seat, or even 
in the glove box. It also features Pioneer’s 
Supertuner III Qiiartz-PLL electronic 
tuner, claimed to offer greater sensitivity, 
exceptional handling of multi-path inter¬ 
ference, and increased resistance to signal 


The DEX-P88R has an RRP of 
$999 and is available at Pioneer 
dealers throughout Australia. For 

more information circle 144 on the reader 
service card or contact Pioneer Electronics 
Australia, 178-184 Boundary Road, 
Braeside 3195. 

Improved digital camera from Canon 

Canon’s new PowerShot A5 digital camera is 
stylish and pocket-sized, offering high resolu¬ 
tion images with a low distortion lens, capa¬ 
bilities for high speed capture and storage of 
images, and a range of memory options. 

The PowerShot A5 features a fast 5mm 
f/2.5 lens that focuses accurately and quick¬ 
ly regardless of lighting conditions. Shutter 
speeds are from 1/6 to 1/750 second and 
users have a focusing range from 0.5m - 
infinity or 90 - 500mm in macro mode. An 
810,000 pixel CCD sensor captures the 
images at optimum resolution, and a dedi¬ 
cated IC then ensures high speed image sig¬ 
nal processing so that the image is quickly 
stored whilst maintaining maximum quality. 

Users can select any one of five resolution 
modes (up to 1024 x 768) to allow optimum 

balance of resolution and stored image 
capacity. The camera comes with an 8MB 
CompactFlash card as standard, holding 
between 44 - 89 images in fine mode or 125 
- 236 images in normal mode (dependent on 
JPEG compression). Additional Canon 
CompactFlash memory cards are available 
from 2MB- 15MB. 

The PowerShot A5 comes with both an 
LCD viewing screen and an optical 
viewfinder. The low temperature polycrys¬ 
talline silicon TFT used in the LCD screen 
ensures exceptionally sharp and bright 
images, even outdoors. 

The camera comes with a range of fully 
integrated software to extend its imaging 
capabilities. It measures just 103mm x 
68mm x 32.5mm, weighs approximately 

230g without batteries and has an RRP of 
$1299. For more information circle 143 on 
the reader service card or contact Canon 
Australia, 1 Thomas Holt Drive, North 
Ryde 2113 

Open-panel hifi speaker is 
made in Australia 

The latest version of Lorpen Audio’s HP3 
open panel hifi speaker (due out next 
month) features improved production tech¬ 
niques, revised panel shape, new drivers and 
more elegant styling. This results in a better 
looking and sounding speaker while main¬ 
taining the attractive pricing. 

The HP3 design features four 170mm dri¬ 
vers mounted on a panel of machined 50mm 
customboard. This open panel handles the 
upper bass, midrange and lower high fre¬ 
quencies. The dispersion pattern of sound 
from the panel is described by Lorpen 
Audio as an enhanced dipole radiating pat¬ 
tern — similar to other panel speakers, but 
with better horizontal dispersion. 

Bass frequencies are handled by an inbuilt 

subwoofer system at the bottom of the panel, 
featuring a 210mm bass driver. High fre¬ 
quencies are handled by a dome tweeter 
mounted in the middle of the panel itself. 

This novel design produces a very differ¬ 
ent sound from conventional box designs. 
The HP3s are claimed to have a smooth 
non-fatiguing sound quality, even at loud 
volume levels, and to be able to resolve sub¬ 
tle low level detail. Stereo imaging is 
claimed to be excellent. The high efficiency 
(quoted at 90.5dB) means amplification 
(both valve and transistor designs) can be 
chosen for their overall sound quality, not 
just the power output specification. 

The RRP for the new Lorpen Audio HP3 
system is $2945.00. For more information 
circle 147 on the reader service card or con¬ 
tact Lorpen Audio, 11 Moldavia Walk, 
Osborne 5017. 

ELECTRONICS Australia, September 1998 



WHArS IfVff the ever-changing world of electronics 

SuperDisk goes USB 

Imation Corp has released an external USB 
version of its 120MB SuperDisk drive, 
developed in conjunction with 
Panasonic and announced at 
the recent Mac World 
Expo in New York. It 
was developed 
specifically to mate 
with Apple 
Computer’s new 
iMac computer, and 
SuperDisks will be made 
available to suit it. The drive is 
also compatible with both 720KB and 
1.44MB floppy disks. RRP in the US is 
around US$189. 

‘Third generation’ Olympus digital camera 

Olympus have announced the latest addi¬ 
tion to their award-winning range of 
Camedia digital cameras, the C-840L. This 
provides a resolution of 1.3 million pixels 
(1280 x 960) and includes many new fea¬ 
tures, whilst retaining the popular features 
of the C-820L (which remains in the 
range), including its compact lightweight 
ergonomic design, 

PAL video out and 
SmartMedia card 

image quality is 
achieved by a high 
quality 5.5mm all¬ 
glass aspherical 
f/2.8 autofocus 
lens, low data 
ratios, and a host 
of other sophisti¬ 
cated Olympus 
technologies. In 
addition to a PAL 
video output for 
easy viewing of 
shots on a TV, and 
the built-in colour LCD, users also have 
the option of creating prints directly from 
the camera with the Olympus P-300E 
dye-sublimation printer via its direct con¬ 
nect capabilities. 

Three resolution modes are provided 
(Standard Quality at 640 x 480, High 
Quality at 1280 x 960, and Super High 

Quality 1280 x 960 with least image com¬ 
pression for superior image quality). 
Exposure control allows users to override 
the automatic exposure system +/-1 step 
for lighting compensation, and a sophisti¬ 
cated multi mode flash offers auto, red eye 
reduction, fill flash, and flash off settings 
to accommodate a variety of lighting con¬ 


Files are saved in an industry standard 
format (JPEG) that virtually any image 
editor, word processor or desktop pub¬ 
lishing application can use and recognise. 
With the addition of an optional PCMCIA 
or floppy disk adapter, images can also be 
downloaded without needing cables. 

Slim 14” LCD monitor 

Panasonic has released the new ‘Panaflat 
LC40’ 35.6cm (14”) LCD computer 
monitor, boasting colour reproduction 
and resolution comparable to CRT moni¬ 
tors but with a depth of only 62mm — 
making it well suited for crowded desks. 

The Panaflat LC40 can be used like a 
conventional monitor and has no special 
hardware or software requirements. It 
has an analog interface that plugs into 
any personal computer’s RGB connec¬ 
tor. A 15 pin D-sub connector with 
adapters for Macintosh personal com¬ 
puters ensures compatibility with most 
computer hardware. 

An automatic pixel converter guaran¬ 
tees uniform thickness in both horizon¬ 
tal and vertical lines and natural screen 
appearance at all resolutions. This 
marks a major improvement over previ¬ 
ous LCD monitors, which could not 
display 640- or 800-dot signals accu¬ 
rately at full-screen size. All signal res- 

Macro focussing has also been 
improved, with the ability to focus as close 
as 10cm. There’s also a 2X digital mode 
for closeups in stan¬ 
dard resolution. 
The Olympus C- 
840L uses 3.3 volt 
removable media. 
A 4MB card is 
included with the 
camera, but addi¬ 
tional 2MB, 4MB, 
and 8MB cards can 
be used so there is 
no restriction on the 
number of photos 
that can be cap¬ 

Designed with the 
consumer in mind, 
the camera is light¬ 
weight at 245g, and 
very compact with dimensions of 128 x 65 
x 45mm. It has a large 51mm smudge-resis¬ 
tant LCD screen and carried an RRP of 
approximately $1499. 

For more information circle 146 on the 
reader service card or contact R. Gunz 
(Photographic), Locked Bag 690, 
Beaconsfield 2014. 


ELECTRONICS Australia, September 1998 

olutions smaller than 1024 x 768 are 
converted to display at full-screen 
dimensions, ensuring full use of avail¬ 
able screen space. 

The screen of the LC40 can tilt up to 30° 
for improved visibility, and a keyboard can 
rest on the screen’s stand to conserve desk 
space. A cable cover is provided to hide 
connections at the rear. The LC40 displays 
16 million colours with a minimum bright¬ 
ness of 150cd/m : , and an anti-glare coating 
prevents reflections and dust build-up. 
Power consumption is only 45W. 

The Panaflat LC40 is available from 
specialist outlets for an RRP of $5650. 
For more information circle 148 on the 
reader service card or contact Panasonic’s 
Customer Care Centre on 132 600. 

Ericsson’s ‘Mobile 
Communication Solution’ 

Ericsson Australia has launched its MC 16 
handheld computer, said to provide a one- 
stop, out-of-the-box mobile communica¬ 
tion solution. It allows the user to send and 
receive e-mail. Short Message Service 
(SMS) and faxes, while also enabling 
access to the internet and intranets. 

The MC 16 comes with the DI 27 
infrared modem, which clips onto the base 
connector of any Ericsson 600 or 700 series 
mobile phone, linking the phone and MC 
16 without cables. The DI 27 is extremely 
small, weighing less than 10 grams and, 
unlike traditional PC card modems, doesn’t 
drain power from the computer. 

The MC 16 uses Windows CE 2.0 as the 
operating system, which includes an Inbox 

application. My Ericsson Phone software 
and Ericsson Mobile internet. It weighs just 
442g with batteries and uses a fast RISC 
60MHz processor with 8MB RAM and 
10MB ROM. 

For more information circle 141 on the 
reader service card or contact Ericsson 

3.8kW motorised 
‘ghetto blaster’ 

Pioneer Electronics says its showpiece 
‘Muscle Truck’ represents the ultimate in 
car audio innovation, and is set to ‘turn 
heads’ at selected Australian car audio 
and motor/lifestype shows over the next 
two years. 

Essentially the Muscle Truck is a cus¬ 
tomised 1996 American GMC SLE Crew 
Cab, fitted out with proprietary voice 
recognition technology, anti-theft mecha¬ 
nisms, dual video display screens and a 
slew of amplifiers and speakers produc¬ 
ing enough power output to fill the 
Melbourne Cricket Ground. 

The heart of the sound source is five 
GM-X922 and two GM-X904 class A, four 
channel amplifiers capable of producing 
power levels up to 3800 watts. To supply 
the current needed to drive this arsenal is a 
bank of heavy duty, heavy current Gel-Cel 
70 batteries and IF capacitors, fitted in a 
removable tray seated between two-banks 
of 10 x 12” TSW-1200C subwoofers (20 in 
total) — giving the vehicle ‘more punch 
than Mike Tyson’. 

Additional speakers include a range of 
mid-range, mid sub and tweeter units. 
Front end components include Pioneer’s 
CDX-P5000 50-disc Stacker, CD-VC50 
Voice Control Unit and DEX-P88R Multi- 
CD controller/tuner. Total value of the 
audio components alone exceed $30,000. 

Not much room for the family or taking 
the rubbish to the tip, but a great way of 
showing off Pioneer’s mobile audio gear... ❖ 



Electrical Principles 1 
60 hrs $150 

Electrical Principles 2 
60 hrs $150 

Analogue Systems 
40 hrs $100 

Feedback, Filters & Oscillators 
40 hrs $100 

Amplifiers 2 
40 hrs $100 

Circuit Analysis 1 
60 hrs $150 

For further information contact Jim 
Mark * (03) 5434 1430 or 


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To tap into these resources, 
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ELECTRONICS Australia, September 1998 



Video & Audio 

The Challis Report 

Pioneer's PDP-V401E 

Full Colour Plasma Display 

This month, hard on the heels of his review of Pioneer’s under-$1000 DVD player, our 
intrepid reviewer Louis Challis had the chance to evaluate the first of their new gee-whiz 
plasma flat-screen displays to reach these shores. And its performance just about blew 
him away. There’s just one problem: how can he — and most of us, for that matter — 
contain our frustration until the price of these beasts comes down to a level where we 

might be able to afford one? 

I f you read my report on the Pioneer 
DV505 DVD player last month, you may 
well recall the degree to which the NEC 
PlasmaSync 4200W plasma display 
impressed me. Not only was I excited by the 
latest complementary advances in video tech¬ 
nology, but more significantly 1 extolled its 
virtues. Indeed, I was sufficiently impressed 
that I imparted my feelings to the sales team 
at Pioneer Australia. 1 rather brashly suggest¬ 
ed that as soon as they received 
their first plasma display, I would 
welcome the chance to review it! 

Needless to say, I had expected 
some weeks or even months to 
elapse before they’d take me up 
on this offer. However it all hap¬ 
pened much sooner. In fact it was 
only a week later that Pioneer 
expedited the delivery of the very 
first PDP-V401E into the country, 
straight to my office... 

What could I do? I couldn’t lose 
face and not review it, particularly as 
they supplemented that delivery with 
the first unit of their brand new (groundbreak¬ 
ing) DVL-909 combination (or ‘combo’) play¬ 
er, to assist me in conducting my review. The 
DVL-909 happens to be the first, and possibly 
the only, DVD player in the world which simul¬ 
taneously provides its owner(s) with the ability 
to play Region-4 DVD’s, PAL and NTSC 
laserdiscs, conventional CDs, the next genera¬ 
tion of high resolution CDs, and Video CDs. 

But back to the plasma screen. Pioneer’s 
PDP-V401E has an immediate and pragmatic 
attraction in that, unlike the NEC PlasmaSync 
4200W, which has been optimally configured 
for a 16x9 widescreen format display, the 
PDP-V401E has been sensibly designed to 
satisfy the more common conventional 4x3 
format — which is the basis for the majority 
of current Australian and other international 
TV transmissions. The 4x3 format is also that 
still preferred for the majority of computer 

and related video displays. 

The PDP-V401E’s designers have focused 
their initial product in satisfying the demand¬ 
ing requirements of the lucrative commercial 
market for large displays. That market craves 
for a display system with minimal depth, 
maximum brightness and one that can simul¬ 
taneously, or more specifically sequentially, 
fulfil the diverse requirements of commercial 
transportation, educational and residential 

A diagram available on Pioneer’s web 
site, giving an idea of the cell 
construction used in its PDP-V401E 
plasma screen. 

requirements and applications. 

The more critical commercial applications 
generally impose an added requirement 
involving the ability to display a computer 
screen’s output in a normally illuminated 
room. That requirement prejudices the 
majority of conventional projection TV’s 
and more significantly virtually all rear-pro¬ 
jection TV sets, which only really function 
adequately in an environment with relatively 
low level illumination. 

Pioneer claims to have gone one step fur¬ 
ther than other plasma display manufactur¬ 
ers. They claim to have achieved the high¬ 
est brightness level in the world, with an 
output illumination level of 400cd/nf. That 

illumination is achieved through the adop¬ 
tion of what they describe as being an ‘opti¬ 
mum cell structure technology’. 

Pioneer also claims to have achieved a 
high, if not the highest, contrast ratio current¬ 
ly available (150:1), to ensure brilliant colour 
contrast. This is achieved by the adoption of a 
special square plasma cell structure, in which 
each of the complicated individual parallel 
cell structures is incorporated in minuscule 
1.26 x 1.26mm repetitive modules. 

Each individual plasma cell in 
the screen functions on the basis of 
the application of electric charges 
to the electrodes on each side of the 
cellular structure. The charge (or 
should I say the discharge) between 
the electrodes in each module then 
reacts with the rare gas contained 
within the gap to produce an ultra¬ 
violet radiation. It is this radiation 
of energy which energises the 
phosphors on the screen, to create 
the visible light which you observe. 
The light from each sub-module 
combines with the light emitted from adja¬ 
cent pixels to produce the visual images. 

Excellent resolution 

Each PDP-V401E has a complement of 
281,000 individual plasma cells, to gener¬ 
ate a picture with excellent resolution, and 
with what appears to be the largest current 
4x3 plasma display picture size currently 
available. Although the PDP-V401E is 
50mm narrower than the width of the NEC 
PlasmaSync 4200W’s screen, its picture is 
higher, and thus provides an outstanding 
visual display with conventional 4x3 format 
TV, video and computer based software. 

The PDP-V401E provides a grey scale with 
256 increments and an amazing 16.7 million 
possible colours. I’ll have to take their word 
for that, as I currently lack the ability to put 
that specific claim to the test. Fortuitously 

Phosphor (R) 
Phosphor (G) 
Phosphor (B) 
Dialortrk Layer 
Ooto eledrodo 
Bock plate 


ELECTRONICS Australia, September 1998 

there are a large number of objective tests that 
I am equipped to perform. Accordingly, I 
availed myself of the appropriate hardware 
and software based procedures to put the 
PDP-V401E through its paces. 

One of the PDP-V401 E’s nicest features is 
its extremely slim profile. With an overall 
thickness of only 100mm, and its adoption of 
a series of five miniature cooling fans along 
the right hand side of the rear panel (when 
viewed from behind), it can be placed up 
close to a rear or supporting wall without 
significant inhibition. 

With a sound reflective rear wall behind, 
the resulting noise level at a distance of 2m 
from the face of the display is only 36dB(A). 
That sound level, although audible in the 
absence of audible program material is suffi¬ 
ciently low to ensure that you are all but 
oblivious to the presence of the fans, until 
you walk up to the display unit and thereby 
detect their presence. 

The PDP-V401E incorporates multiple 
inputs, which are located in a line along the 
lower rear edge of the unit’s perimeter fram¬ 
ing. These provide direct connection for vir¬ 
tually all forms of conventional video signal 
(NTSC, PAL and SEC AM), as well as SVGA 
or Mac computer graphics inputs. The unit 
also incorporates an RS-232 port, through 
which you can exercise computer control of 
the images. 

I examined the display’s output when fed 
with video signal from a Power Mac 
9500/120, and the latest generation of SVGA 
inputs from a 225MEIz Pentium II computer. 
With both of those formats I was able to pro¬ 
duce truly superlative displays. 

Field trials... 

The Pioneer PDP-V401E and Pioneer DVL- 
909 combo player arrived just in time for the 
weekend. Fortuitously Columbia Tristar 
Pictures responded to a long standing request 
to provide me with a copy of MatilJa , the first 
of their G classification DVDs suitable for 
young children’s viewing. As it happens, that 
was also the weekend on which my grand¬ 
children were sleeping over. I thus had the 
perfect opportunity to field trial the system. 

My grandchildren’s response was truly 
ecstatic, and both the big-screen hardware 
and the exciting software were an immediate 
hit. When I finally managed to drag them 
away from the PDP-V401E, the first ques¬ 
tion they asked was “When’s daddy going to 
get a TV like this?' (That’s the one question 
to which 1 delicately avoided a response!) 

The PDP-V401E’s brightness level was so 
high that we were able to watch the video 
with all of my living room’s full complement 
of lights and supplementary reading lights 
switched on. The most exciting aspects of 
that evening’s foray into this new video tech¬ 

nology were the PDP-V401E’s brightness 
levels, its outstanding colour balance and its 
visual ambience, all of which were as close to 
being optimum as I could have hoped for. 

Needless to say, my grandchildren were just 
as excited as I was. But more significantly, it 
was obvious that the larger screen size, and its 
realistic visual impact, created a degree of real¬ 
ism that eclipsed anything they had ever expe¬ 
rienced when watching a conventional TV set, 
or even when viewing a cinema screen. 

It was only later, following the children’s 
departure to their respective beds that 1 was 
able to sit down and experiment with the 
plasma display’s user controllable settings, 
using the PDP-V401E’s remote control... 

Actually I only discovered that there was a 
remote control when I picked up the hand¬ 
book and noticed it listed — which led me to 
look for it in its carton. I then discovered that 
the unit’s default settings conformed to the 
settings that I would have chosen had I 
selected them myself. 

During the objective testing that followed, 
I was unable to fault the quality of the PDP- 
V401 E’s display linearity nor its colour real¬ 
ism. It was only when I sat within 3m of the 
screen that I was able to observe the pres¬ 
ence of individual pixels. There are 281,000 
of those, and I had to look carefully before I 
was able to identify them with still pictures. 

The next morning my grandchildren plead- 

ELECTRONICS Australia, September 1998 





The new VAF DC-X is a genuine 
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The Challls Report 

ed for yet another DVD, so we briefly viewed 
half of a ‘G rated’ NTSC-format DVD on a 
Region 1 (US) DVD Player. With only 525 
vertical lines of resolution, NTSC DVD’s pro¬ 
vide an inferior picture when compared to the 
625 line PAL-based Region 4 software that we 
had viewed the previous evening. 

Following my grandchildren’s departure, 1 
was able to devote further time and attention 
to assessing other parameters that would have 
been of little interest to a child. Some of those 
parameters will be of significant interest to 
some readers, and were evaluated as a result 
of questions which were initiated by other 
recently completed reviews. I used both DVD 
and laser disc based test software to derive the 
following information: 

1. Vertical and horizontal linearity: These 
proved to be as close to perfection as one 
could ever desire. 

2. Colour smear: This is clearly visible with 
laserdisc software, but much less evident 
and almost invisible using NTSC-format 
DVD test software. 

3. Uniformity of grey scale display: This is 
very good with laserdisc software and quite 
outstanding with DVD test software. 

4. ‘Multi-burst’ linearity: This exceeds 
4MHz with laserdisc software and appears to 
achieve a marginally higher figure with 
DVD test software. 

5. Contrast ratio between maximum white 

and maximum black: This is excellent with 
laserdisc software and again superior with 
DVD test software. 

6. Cooling fan noise emission at various 
points in the viewing region in front of the 
display: Virtually inaudible in the zone on 
the right hand side of the screen, just audible 
in front of the screen, and readily audible in 
the zone to the left hand side of the screen — 
measured level of 36dB(A). 

7. Angular range of viewing: This exceeded 
145° in the room in which we were viewing the 
PDP-V401E. Note that the manufacturer claims 
160° horizontal and vertical viewing angles. 

In summary 

Pioneer were kind enough to leave the PDP- 
V401E and the DVL-909 with me for 10 
pleasant days of viewing. During that period, 
I was able to confirm, and indeed simply 
cannot deny that the PDP-V401E viewing 
quality and sense of realism eclipses that of 
any conventional TV monitor screen, projec¬ 
tion TV monitor display, or rear projection 
TV display that I have yet seen. 

The PDP-V401E’s plasma display has the 
ability to uplift and upstage your current per¬ 
ceptions of what you desire for your home 
cinema or your general (or private) TV view¬ 
ing. As you will undoubtedly discover when 
you finally get the opportunity to view one, 
plasma displays like the PDP-V401E simply 
set a new standard, and become the bench¬ 
mark against which we will now assess 
video quality. ♦> 

Pioneer PDP-V401E Full Colour Plasma Display 

A multiformat plasma-based display screen for both video (PAL/NTSC) and computer graphics 
(SVGA/MAc). Measures 946 x 740 x 100mm, weighs 30kg (unpacked), displays in 4:3 format. 
Good points: Excellent image resolution (281,000 pixels), very high brightness (400cd/m 2 ) 
and contrast ratio (150:1), wide viewing angle (160°). 

Bad points: Low level noise emission from cooling fans. For many of us, price will be the only 

RRP: About $17,000. 

Available: Pioneer dealers, or contact Pioneer Electronics Australia, 178-184 Boundary Road, 
Braeside 3195. 

At last! 

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by Peter Phillips 

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Expanding Possibilities 

Digital Cameras 


Prices Still 

Digital still cameras are now 
getting quite serious in the 
consumer market. Their picture 
quality continues to rise, while 
prices are descending and sales 
are rising. While the bulk of 
happy snappers are yet to swing 
over, and film technology still 
has the edge in terms of 
performance/price, more and 
more enthusiasts are 
succumbing to the lure of 
instant ‘megapixel’ imaging. 

by Barrie Smith 

A re digital cameras a serious competitor 
to traditional silver halide film cam¬ 
eras? Not by a long chalk — yet. 
Incredibly, you can still buy a $5 plastic, 
fixed focus kiddie’s camera, drop a roll of 
film in and get better 10x15cm prints — 
judged by serious, critical standards — than 
most digital cameras on the market below 
$ 2000 . 

So, for the short term — say two or three 
years — it looks as though digi cams will not 
so much sit side-by-side or replace the tradi¬ 
tional cams, but establish a market sector all 
their own. 

Current market leaders are those from 
Olympus, Kodak and Sony; but no manufac¬ 
turer claims to be making money out of the 
product at this time. So, with much talk — 
especially in the Australian market — of fin¬ 
gers being burnt by the smaller players, the 
majors prepared to invest heavily in digital 
camera development are still hanging in there. 

What is becoming apparent is that digital 
camera sales follow on alongside sales of 
PCs. A prime case at the moment is New 
Zealand, which is showing eager growth in 
both product lines. 

The Web is also driving digital cameras; 
the devices’ ability to output a small, ade¬ 



Kodak’s new top of the range DC260, with a 1.6- 
million pixel CCD coupled to a 3X zoom lens. 

quate resolution file direct to the computer is 
heaven-sent for eager emailers, attaching 
all sorts of imagery to their messages. This 
writer is forced to admit to flooding the 
network last Christmas with 80 worldwide 
email messages — photos attached; be 
thankful you were not on my list! 

Digital cameras are definitely not being 
adopted by the happy family snapper 
brigade, nor the keen SLR enthusiast — for 
obvious reasons: as yet, the quality is ‘not 
there’. Many are also put off by the 
downloading trauma and the fid¬ 
dling needed to extract photo quali¬ 
ty from current inkjet printers. 

But, with regard to the latter, 
inkjet printers are winning a multi¬ 
tude of friends every moment of 
every day; new models by HP, Canon 
and Epson are outputting colour and 
resolution indistinguishable from con¬ 
ventional colour prints in many 
respects. It is a bit of a fiddle — but 
one that this writer for one is 
happy to undertake! 

Nikon’s Coolpix 900 not only features a 
swivelling case, for flexibility, but also a 
1.3M pixel CCD and a nine-element 
Nikkor lens. 


ELECTRONICS Australia, September 1998 

Sharp-eyed sensors 

Megapixel models 

The current buzz in the industry 
centres around which manufacturer 
has launched a megapixel camera or 
even a ‘megapixel plus’ model. 

Megapixel? Basically the term means 
a camera able to output a file of one mil¬ 
lion pixels. In most units at this level the 
CCD itself possesses one million picture 
elements (pixels) so the output is a gen¬ 
uine megapixel picture. But some do 

Above left is the Olympus C-1400L, which 
boasts a 1AM pixel CCD coupled to a 3X 
zoom lens; above right is the Fuji MX-700, 
with a 1.5MB CCD and a 35mm equivalent 
lens; and below is the Konica Q-M100, 
with a 1.08M pixel CCD and 6mm lens. 

At this point in a maturing market, the 
appeal of a CCD of megapixel — or bet¬ 
ter! — resolution is undeniable. If you are 
making digital camera images for repro¬ 
duction in a glossy colour magazine 
(using a 150 lines per inch dot screen), a 
1280 x 1024 pixel image will permit 
acceptably sharp reproduction to 10.8 x 
8.67cm. If sharp-eyed critical assessment 
— and the test charts — are put aside, it is 
possible to get a very acceptable A5 (half 
A4) printed image. 

For the home and office user, an image 
from a camera of this resolution level is 
easily enlarged to near-A4 page size with 
high level printers such as Epson’s Photo 
EX inkjet, which boasts 1440 dots per inch 
resolution on the ‘photo gloss’ paper. 
What comes into play is viewing distance 
for photographs and the like; nobody 
peruses a 10 x 8 (or an A4) print at less 
than arm’s length. 

‘fudge’ — like the Kodak DC 120 model, 
which in truth has an 836,000 pixel CCD, 
but outputs a 1280 by 960 pixel picture com¬ 
posed of 1,228,000 pixels (1.23M) — 

accomplished by in-camera interpolation. 
Other Kodak models — the DC200 and 
DC210 — have actual 1.01M CCDs 
(1152 x 864 pixel images). 

The newish Fuji MX-700 model 
boasts a 1.5M pixel CCD (1280 x 1024 
pixel image), while its companion 
model the DS-300 offers 1.3M (1280 x 
1000 pixel image). 

Konica has its Q-M100, with a 
1.08M CCD (1152 x 864 pixel image) 
- a straightforward camera embell¬ 
ished by a bevy of Photoshop plug-ins 
to titillate captured images. 

Nikon, in its 1.3M CCD Coolpix 900 
camera, delivers a 1280 x 960 pixel image 
with the added cachet of a nine element/seven 
group Nikkor lens using aspheric glass ele¬ 
ments. Three exposure modes are to hand — 
spot, centre-weighted, matrix. 

Raising resolution... 

As digital camera manufacturers strive to 
lift resolution levels, camera software devel¬ 
opers are also seeking to help the cause. 

It seems that fractals may provide 
some of the solutions. As mentioned in 
the text, some cameras employ pixel 
interpolation to raise their image cap¬ 
ture’s apparent overall resolution. This 
action relies on internal processing to cre¬ 
ate new additional pixels, derived from 
adjacent CCD pixels. 

An exciting approach has also been pur¬ 
sued by the US Altamira Group. In creating 
Genuine Fractals, the company has devel¬ 
oped a plug-in for Adobe Photoshop soft¬ 
ware which allows the creation of very 
small files from comparatively large files, 
and vice-versa. It’s essentially a lossless 
compression system. As an example, a 
640 x 480 pixel image of 307KB could be 

created from a 2000 x 1500 pixel file of 
around 8MB, and scaled up again at will. 

Whilst not being taken up by any camera 
manufacturer at this stage, fractal tech¬ 
niques look likely to help reduce the size of 
images transmitted via the Internet — yet 
maintain and even improve their quality. 

Believe it! You can download a free trial 
version from the company’s Web site at 

...and lowering it again! 

Some camera designers (or is it the 
marketing people?) seem to have missed 
an essential point in digital camera strat¬ 
egy: getting the resolution levels up — 
and with it, final picture sizes — is the 
name of the game. 

In spite of this, the dreaded ’digital zoom’ 
facility has crept in from the world of video 
camcorders (where levels of digital zoom 
have reached 100X and more). So we see 

digital still cameras from Epson, Casio and 
others incorporate this feature. (All a digital 
zoom does is effectively crop the CCD sen¬ 
sor image, using digital enlargement of the 
centre portion. This essentially throws 
away’ some of the sensor’s resolution...) 

The Epson PhotoPC 600 offers a 3X dig¬ 
ital zoom, while the yet to be released PC 
700 pulls this back to 2X. In the US and 
Japan Casio’s QV-5000SX has a 2X/4X 
digital zoom; the Fuji MX-700 features a 
‘playback zoom’ of up to 4X, which allows 
you to closely inspect a shot — but at 
least it does not crop and enlarge the 
pixel array as with the Epson models. 

Enlarging, say a 1024 x 768 picture by 
2X seems a pointless exercise when you 
can do it with far more control in image 
editing and manipulation software. 
Besides, who really wants to throw useful 
pixels away when in fact you need every 
one you can get! 

ELECTRONICS Australia, September 1998 


Digital Cameras Update 


At the top end 

Olympus long ago found its place in the 
top three by devoting considerable atten¬ 
tion to the lens optics in its models. The C- 
1400L uses a 2/3-inch CCD (most other 
models use a 1/3” CCD) containing 
1,410,000 pixels, creating a 1280 x 1024 
pixel image. The lens is all-glass and uses 
aspherical elements to apply a high level 
of correction; its optical resolution of 160 
lines/mm at the centre is close to that of 
topline 35mm compact film cameras. 

Obviously aware that the educated buyer 
was flocking to the Olympus, Kodak 
moved into high gear a few months ago by 
releasing two new cameras. 

The Kodak Digital Science DC220 and 
DC260 zoom digital cameras are the first 
consumer digital cameras to use a 
Motorola PowerPC processor to speed 
image processing and customise camera 
operations. The DC220 has near-one mil¬ 
lion pixels (an image of 1152 x 864); while 
the DC260 has a 1.6 million pixel CCD 
(1536 x 1024) and can capture enough 
detail for a photo-realistic 8 x 10” picture. 
Other niceties include a Burst Feature 
which can capture in each second up to 
eight pictures at standard resolution or two 
pictures at high resolution. 

Both cameras allow you to record audio 
to accompany your photos. A scripting 

Above is Sony’s Digital Mavica MVC- 
FD71, which although offering only 640 x 
480 resolution also boasts image storage 
on standard 1.4MB floppy disks. At left is 
their Mavicap floppy disk recorder, which 
captures to a floppy disk any image from 
a PAL camcorder or any video source 
with an analog output. 

feature can instruct your camera to per¬ 
form a series of pre-set actions, such as 
take multiple pictures at pre-set intervals 
or adopt program camera settings for dif¬ 
ferent picture-taking conditions. 

The DC260 has a lens with 3X optical 
plus 2X digital zoom — this means the 
unfastidious can ‘zoom in’ to 6X; the 
camera offers a useful extra in that it can 
connect to an external flash, allowing 
lighting of increased subtlety and power. 
And notice the very different aspect ratio 
of 1.5:1 — identical to a 35mm frame. 

Spreading the resolution 

A novel and quite fascinating piece of software, PhotoVista 
(from Live Picture), comes to the rescue of all those keen to 
create sectional panoramas — and so magnify camera resolu¬ 
tion levels. 

You begin by shooting a series of linking and overlapping still 
shots. These can be made with a digital or traditional camera 
and either input directly from the camera or converted by scan¬ 
ning. The software then embraces the separate pieces of the 

panorama and 'stitches’ together all sections to make a com¬ 
plete, seamless wide image. 

To use it is to be amazed at the ingenuity that has obvious¬ 
ly gone into its creation; overlapping straight lines meld, hori¬ 
zons blend, adjoining textures merge. The software (Win and 
Mac) costs $145 (Maxwell Imaging is the distributor). 

Other makers in the US have created similar applications, 
while Olympus and Canon market camera models which have 
a panorama stitching feature that produces output similar to 


ELECTRONICS Australia, August 1998 

Sony’s Digital Mavicas 

While this story is ostensibly about 
megapixel cameras, the inescapable fact is 
that the whole market is being led by a cam¬ 
era offering only a maximum 640 x 480 
pixel image. The Sony Digital Mavica — in 
two models — accounts for 40% of total dig¬ 
ital camera sales worldwide. 

The attraction is that the Digital Mavicas 
use the humble, venerable, universal (and 
cheap) 3.5-inch HD floppy disk for image 
storage. It’s hard to beat the convenience of 
shooting a batch of pics, discharging the 
floppy and then dropping it into your PC’s 
drive to look at them. 

And what about the price? Other cameras 
use PC cards which can cost in the hun¬ 
dreds of dollars. A floppy can cost as little 
as 50 cents... 

Now the company has delivered to market 
two new models, the FD51 and FD71 — 
plus a clever unit, the Mavicap, based on 
Mavica internals. 

The higher level FD71 has a progressive 
scan CCD and a new, thin high-speed floppy 
disk drive, nearly doubling the speed of 
recording and playing back images. The 
camera’s ‘whole disk copy’ mode also 
makes a copy of an entire disk full of 
images, with some dexterous disk swapping. 

The FD71 has internal RAM to accomplish 
this task — and the feature is not limited to 
images. Other computer files can be copied 
from disk to disk as well. 

The new camera’s standard mode saves up 
to 40 pictures on a single floppy disk as 640 
x 480 PC JPEG files, while the fine mode 
stores up to 20 at half the compression of the 
standard mode. For higher-quality pictures, 
a non-compression mode stores images as a 
near-megabyte BMP file. 

The FD71 also has an e-mail mode that 
reduces the size of the image to 320 x 240 
for smaller file size and faster transmission. 

Borrowing on Sony’s camcorder exper¬ 
tise, the Mavica has a 10X optical zoom 
lens, macro capability and a manual focus 
ring for accurate focusing; and a full- 
motion, 2.5” colour LCD display 
viewfinder with a solar window. The solar 
window uses sunlight to enhance backlight 
for the display, for better viewing in bright 
light with minimal battery drain. 

The camera has a huge advantage in the 
digital still camera market by employing a 
camcorder battery — the rechargeable 
InfoLithium unit that powers the taking of 
up to 500 consecutive shots. 

Although it’s not a camera, the Mavicap 
Floppy Disk Recorder is interesting 
because it allows capture of any image from 
a PAL camcorder or any video source with 
an analog output, and storage on a standard 
floppy disk. In effect, then, the floppy disk 
recorder transforms a camcorder into a dig- 

ELECTRONICS Australia, September 1998 

Table 1: A Comparison of Current Models 

Manuf/Model Lens Shutter Speeds Pixels/Resolution Viewfinder Price(RRP) 


QuickTake 200 







ePhoto 307 






ePhoto 780 






ePhoto 1280 

3X zoom 






PowerShot 600 


























Photo PC600 


























f2.5/33-105mm 1/4-1000 













f2.5/37-lllmm 1/16-1/500 





f2.5/38-114mm 1/16-1/500 

















f4-16/29-58mm 1/2-1/360 























Dimage V 

f5-5.6/2.7X zoom1/30-1/10,000 





Coolpix 100 






Coolpix 300 






Coolpix 600 






Coolpix 900 

























2.8/3X zoom 






f2.8/3X zoom 













R DC-300 

















































Notes: Some cameras appear on the market as rebadged models: Konica’s Q-mini, Canon PowerShot 
350 and Panasonic’s DCF1A are, for all intents and purposes, identical — as is Hewlett-Packard’s HP. 


Digital Cameras Update 

ital still camera. 

The unit has composite and S-video 

So where are we? 

There’s no doubt that digital cameras are 
now, from a marketing point of view, a 
viable product. In Australia alone sales in 
1998 are expected to reach 35,000 — up by 
40% from 1997’s 25,000 figure. 

They are being increasingly accepted in 
business and education circles; because of 
this, there is possibly less criticism applied 
to their technical shortcomings. 

All the same, it’s doubtful if a keen ama¬ 
teur photographer, let alone a pro, would 
accept their remaining deficiencies. Like: 

• Virtually all of the latest digi cams sport 

an LCD finder; these draw power at an 
alarming rate. The hapless alkaline cells 
frequently supplied with digi cams are 
totally inadequate for the task. The ideal 

CMOS sensors? 

In our previous report on digital 
cameras (EA December 97), mention 
was made of the attractions of CMOS 
image sensors, 

Vivitar's ViviCam 3100 is attracting 
attention in the US. It has an 800,000 
pixel CMOS sensor, with a 1920 x 
1600 pixel output image, and is 
claimed to offer 'advanced 30 bit, four 
colour performance’... 

answer seems to be the camcorder batter¬ 
ies employed by Sony and Canon in their 
new models; high shot numbers and easy 
recharging are their attractive benefits. 

• The rated speed of all consumer camera 
CCDs is far too low for general use; 
Nikon’s Coolpix 900 camera rates its 
CCD as equivalent to ISO 64 remem¬ 
ber Kodachrome 64? Most other models 
go only to ISO 100, which is still not too 

• In poor light conditions the built-in flash 
can save the day — but most are too low 
in output for wide shots. 

• The opposing standards of PC memory 
cards — SanDisk’s CompactFlash and 
Toshiba’s SmartMedia — is a problem. 
Some cameras use one, the rest use the 
other — with no converter between. Now 

Above is a night shot taken with the Fuji 
MX-700, which sports an image resolution 
of 1.3 million pixels. At left is an image 
taken with the Nikon Coolpix 900 camera , 
which offers an image resolution of 1280 
x 960 pixels. Below is a shot of the 
Braidwood hotel , taken with a Kodak 
DC200 — with 1.01 megapixel CCD (1152 
x 864). 

it seems likely Sony will develop a 
‘super-floppy’ capable of 200MB! 

It will certainly be interesting to see 
what the future holds in this fast-moving 
market area. 

(Barrie Smith is editor of Australian 
Digital Camera magazine.) ❖ 


ELECTRONICS Australia, September 1998 

Hong Kong 


Oct 13-16, 1998 

Hong Kong Convention & 
Exhibition Centre 

There is no better place to obtain the latest on electronics than Hong Kong 
Electronics Fair '98. Over 1,200 exhibitors will be there to show consumer 
electronics, electronic components and technology. In addition, there are 
numerous concurrent events to satisfy buyers' needs: 

• "The Frontiers of Brainpower" - for innovative concepts, prototypes of 
technology and product research with ample opportunities for business 

• "electronicAsia" - jointly organized with Germany's Messe Miinchen 
International (MMI), for electronic components, assemblies and 
production gear 


SU sisni»Kfi 

Hong Kong Trade Development Council 

• "LaserAsia" - a Asian trade fair for laser technology and technical optics, 
co-organized with MMI 

• "Asian Electronics Forum" - for the latest market trends and technological 

Level 3, Hong Kong House 
80 Druitt Street 
Sydney N.S.W. 2000 

Tel : 61 -(02)-9261 -8911 Fax : 61 -(021-9261 -8966 

E-mail : 

Web Site: 

Official Air Express Co.: 

• "PCIM Conference" - for Power Electronics, Drives, Motion and Control 
Be ready for the 21st Century. Be there at Hong Kong Electronics Fair '98. 

Fair Opening Hours 

October 13 

9: 30am - 

10: 00 pm (Opening Ceremony) 

10: 00am - 

6: 30pm 

October 14-15 

9: 30am - 

6: 30pm 

October 16 

9: 30am - 

5: 00 pm 

Official Carrier: 

Cathay Pacific 

Trade only. Visitors under the age of 18 will not be admitted. 


Camedia C-1400L 

Digital Camera 

There’s no doubt that Olympus is 
continuing to take a leading role 
in the accelerating development 
of digital cameras. We recently 
had the opportunity to try out its 
current flagship model, the C- 
1400L — boasting a 1.4-million 
pixel CCD sensor, coupled to a 
3X power zoom lens with true 
TTL single-lens reflex viewfinder, 
and using SmartMedia 
removable memory cards. 

by Jim Rowe 

W hen I reviewed the Olympus C-800L 
digital camera this time last year, I 
wrote in the summary box “If it had a 
zoom lens for easier closeups, an SLR-type 
viewfinder and perhaps could take extra plug¬ 
in cards for even more memory, our wish list 
would be totally fulfilled”. 

Well, with the new C- 
1400L they’ve come very 
close to doing it. 

The C-1400L has an 
all-glass seven element 
3X power zoom lens, 
covering the focal length 
range of 9.2 - 28mm 
(equivalent to 36 
110mm in familiar 35mm 
camera terms), and with a 
maximum aperture vary¬ 
ing from f/2.8 at the wide 
angle end to f/3.9 at the 
tele end. The rated resolu¬ 
tion of the lens in the cen¬ 
tre is better than 100 
lines/mm, higher than the 
lenses in many 35mm 
SLRs. And it has a true 
SLR-type TTL (through 
the lens) optical viewfind¬ 
er, for parallax-free image 
composition. It even has plug-in SmartMedia 
memory cards, although these are now 
instead of the fixed internal 6MB memory in 

the C-800L, rather than in addition to it. Oh 
well, we can’t have everything, I guess... 

On the other hand, the C-1400L does have 
a new and improved 17mm (2/3”) progres¬ 
sive-scan 1.4 million pixel CCD image sen¬ 
sor, delivering a maximum image resolution 

A handheld shot (HQ mode) with the 
zoom lens at the tele end, taken on the 
seashore of Botany Bay, on a dull 

of 1280 x 1024 pixels. That’s an improve¬ 
ment of about 66% over the interlaced-scan 
CCD used in the C-800L, which delivered a 
maximum resolution of 1024 x 768 pixels. 
And the progressive-scan technology does 
provide improved colour rendition and 
reduced fringing. 

As before, the C- 
1400L offers such nice 
features as autofocus (by 
contrast detection), spot 
TTL exposure metering 
and compensation for 
back lighting (seven 
steps). The lens also fea¬ 
tures a special Olympus 
compact prism for the 
SLR system, reducing 
overall weight and elimi¬ 
nating the moving mirror 
and its mechanical shock. 

The lens again has a 
macro range, focussing 
from 300mm to 600mm 
in addition to the normal 
range of 600mm - infin¬ 
ity. This doesn’t let you 
get quite as close as the 
200mm of the C-800L, 
but on the other hand the 
longer focal length brings you visually 
closer. There’s two ‘Quick Focus’ settings 
of either 400mm or 2.5m, to speed up 


ELECTRONICS Australia, September 1998 

shooting in typical situations. 

The zoom lens fitted to the C-1400L 
actually seems to have only two aperture 
settings, f/2.8-3.9 and f/5.6-7.8. The 
remaining exposure adjustment seems to 
be via shutter speeds, 
which vary between 1/4 
and 1/10,000th of a sec¬ 
ond. Not that the user is 
normally aware of this, 
of course. The effective 
sensitivity of the cam¬ 
era’s CCD sensor is 
ISO 100 — not super 
sensitive, but OK for a 
lot of photography. 

As noted the C-1400L 
stores its images in slim 
SmartMedia removable 
memory cards (also 
known as SSFDCs or 
‘Solid State Floppy Disk 
Cards). These operate on 
3.3V and are made by 
Toshiba. They slip into a 
slot at the right-hand rear 
of the camera, accessed 
via a swing-out door. 

The C-1400L comes 
complete with a 4MB card which can store 
between four and 49 images depending on 
the resolution mode you’ve set. 

There are three resolution modes avail¬ 
able on the C-1400L, labelled SQ, HQ and 
SHQ in ascending order of effective image 
resolution (and file size/downloading time). 
SQ or ‘standard quality’ gives 640 x 512 
pixel images, and it’s this mode in which the 
4MB memory card will store 49 images. 
The HQ or ‘high quality’ and SHQ or ‘super 
high quality’ modes both deliver images of 
1280 x 1024 pixels, but with greater or less¬ 
er amounts of compression respectively. It’s 
in the SHQ mode that the 4MB card will 
only store four images; in HQ mode this 
rises to 12 images. 

So although the C-1400L does offer con¬ 
siderably better image resolution than say 
the C-800L, plus the convenience of 
SLR/TTL operation and a zoom lens, there 
is a price to pay in terms of image storage 
with the included 4MB memory card. With 
the C-800L, you could store up to 30 
images of 1024 x 768 pixels in the built-in 
6MB memory. 

Of course with the C-1400L you can 
always get additional 2MB and 4MB 
cards, and swap cards as they become 
filled. Olympus also notes in its literature 
that 8MB and larger cards are likely to be 
available soon. 

Another important advantage of using the 
removable SmartMedia cards is that they 
provide an additional avenue for download¬ 
ing the images to your computer. In fact one 
of the optional accessories Olympus has 

available for use with the C-1400L and its 
other models using SmartMedia memory 
cards is a special adaptor which accepts the 
cards and slips into a standard 3.5” floppy 
disk drive, to allow the PC to read from and 

A closeup taken with the macro facility, at 
minimum distance. The colour 
temperature is low as incandescent 
lamps were used. 

write to them directly, as if they were a flop¬ 
py. (You need to load a small driver utility to 
do this — the utility is supplied on floppy as 
part of the adaptor kit.) 

Downloading images via the card adaptor is 

potentially rather faster than using the RS- 
232C serial cable system used with the C-800L 
and other earlier models, but the C-1400L still 
provides this option if you prefer. Or if you 
have a machine running Windows NT4, with 
which the adaptor utility 
isn’t compatible... 

By the way the C- 
1400L also has a high 
speed parallel output 
port, which can be used 
to download images 
directly to the optional 
Olympus P-300E dye 
sublimation printer. That 
way, you can get colour 
prints immediately, with 
no need for a PC. 

The C-1400L also 
includes a flip-up variable 
output electronic flash, 
with three operating 
modes: autoflash (fire 
when needed), fill (always 
flash) and red-eye reduc¬ 
tion (multiple flashes, to 
reduce a subject’s pupil 
size). Needless to say the 
flash is automatically dis¬ 
abled in the ‘down’ position. 

Other features continued in the C-1400L 
include a 45mm diagonal TFT colour LCD on 
the rear of the camera, to allow convenient 
reviewing of the shots you’ve taken; automatic 
time and date ‘stamping’ of each shot; the abil¬ 
ity to selectively erase unwanted shots from 
memory, to free space for more shots; and 
focus locking with the release button pressed 
halfway in. As with earlier Olympus models 

At the rear, 
there ’s a 
45mm TFT 
LCD screen for 
reviewing your 
pictures, as well as 
the TTL viewfinder — 
which has dioptre 
adjustment, by the way. 
The camera is quite 
intuitive to use. 

ELECTRONICS Australia, September 1998 



Olympus C-1400L Review 

Olympus Camedia C-1400L Digital Camera 

An advanced digital still camera taking images at up to 1280 x 1024 pixel 
resolution. Features a seven-element 3X power zoom lens (equivalent to 36 - 
110mm on a 35mm camera), with true SLR-type viewfinder, autofocus and TTL 
spot metering. Stores images in removable SmartMedia memory cards. Built-in 
flash and 45mm colour TFT LCD screen for reviewing images. 

Good points; High image resolution, colour rendition with improved progressive 
scan CCD sensor; zero parallax error with SLR viewfinder. Fast image downloading 
via SmartMedia floppy adaptor. Basically, excellent image quality and operating 

Bad points; Very little, apart from the price. 

RRP: $2499. 

Available: From digital camera dealers, some photographic stores. For your nearest 
supplier contact distributor R. Gunz (Photographic), 2/26-34 Dunning Avenue, 
Rosebery 2018; phone (02) 9935 6600 or fax (02) 9935 6622. 

it’s powered from four AA-size batteries, of 
either the alkaline or NiMH or NiCad type. 

The C-1400L is compact, measuring 115 x 
130 x 83mm and weighing a modest 470g 
without batteries or memory card. It comes 
complete with lens cap, carrying strap, bat¬ 
teries, RS-232C serial cable (with Mac adap¬ 
tor), a 4MB SmartMedia card, manuals and 
two CD-ROMs containing the Olympus util¬ 
ity software and a bundled image editing 
application (Adobe’s Photo Deluxe). 

Options available include an AC power 
adaptor, a set of NiMH rechargable batteries, 
a battery charger to suit, a carrying case, the 
SmartMedia floppy adaptor kit and of course 
the P-300E colour printer. 

Trying it out 

Olympus distributor R. Gunz (Photographic) 
very kindly made a sample C-1400L available 
for a few days, so I could try it out for myself. 

I was able to try it in a variety of situations, 
and compare its performance with other cam¬ 
eras I’ve used of both the film and digital type. 
Frankly I’m most impressed. The image 
quality is excellent, particularly in the top 
SHQ mode but also in the HQ mode. There 
seems to be very little of the edge fringing 

visible on earlier models, and the colour gra¬ 
dation also seems a lot smoother. 

I have the impression that the zoom lens 
sharpness isn’t quite as good as on the C- 
800L’s fixed 5mm lens, especially at the 
tele end, but it’s still very good indeed. 
Hopefully you’ll get at least a reasonable 
idea of the image quality possible from the 
sample shots included here — which are not 
retouched at all, just converted to CMYK 
format for printing. 

Overall the operating convenience and the 
potential image quality achievable with the 

C-1400L seem very comparable with a typ¬ 
ical good quality 35mm SLR. About the 
only area of unfavourable comparison now 
is cost; by the time you add an extra 
SmartMedia card or two for storing enough 
shots for a trip or whatever, you’re still pay¬ 
ing a considerable premium for the conve¬ 
nience of digital photography. Hopefully 
this will continue to improve with time. 

All the same, Santa can certainly bring me a 
C-1400L if his budget allows. And if you get 
a chance to try one out for yourself, you’ll 
very likely want one too... ❖ 

Scan Audio's 
1998Speaker Drivers 
and Kits Sale. 




Peerless, Vi fa drivers up to 50% off! 
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Presenting our annual sale for 1998. We welcome your enquiry & order by telephone fax, or e-mail. One flat delivery 
fee of $10.00 applies to each order. Orders despatched next business day. Data on these drivers is available in our 
comprehensive 106 page catalogue with full factory data sheets on every Vifa, Peerless, Dynaudio and Scan-Speak 
driver we sell. Catalogue costs $15.00 which includes air mail postage anywhere in Australia or New Zealand. 


Free info available, includes specifiactions on most drivers. 

Limited stocks expected to sell out quickly. 
Hurry! Phone/fax/e-mail your orders in now! 

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Fax(03) 9429 9309 E-mail 



audio ' 

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Huge range of VIDEO 

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k. A 



2/1 Leonard Street, HORNSBY, NSW, 2077 
P O Box 548, WAHROONGA, NSW, 2076 
Fax (02) 9477 3681 Ph. (02) 9477 3596 
Email questav( 
Visitors and demo's by appointment only. 


ELECTRONICS Australia, September 1998 


MHcroGram Computers 

PCMCIA Video Capture Card 

PCMCIA Video Capture card com¬ 
plete with software. Designed to 
provide smooth, full-motion video 
for applications such as Video Mail, 

Video Conferencing or Full-Motion Video Capture to 
AVI file format. The Video Capture card is WIN 95/98 
compatible for easy installation & setup. Provides 640 
x 480 resolution with 30fps capture rate. 

Cat. 3375 PCMCIA Video Capture Card $739 

VGA Monitor Splitters 

These splitter modules enable up 
to 16 monitors to share the same 
information of a host PC simulta¬ 
neously. The ideal way of providing multiple displays 
in training rooms, airport terminals, stock rooms, 
clubs, etc. The splitter may be up to 15m from the 
computer while the monitor may be up to 100m from 
the splitter for the 2 way module & up to 50m for 4, 8, 
12 & 16 way modules. They are suitable for VGA, 
Super VGA and XVGA monitors. 

Cat. 3070 

VGA Splitter 2 Way 


Cat. 3055 

VGA Splitter 4 Way 


Cat. 3056 

VGA Splitter 8 Way 


Cat. 3349 

VGA Splitter 12 way 


Cat. 3350 

VGA Splitter 16 way 


PCI Plug & Play Serial Cards 

Provide 4 RS232 Serial ports with 16650 UARTs 
(32Byte FIFO buffer). Data transfer rate is from 50 to 
921,600 Baud. The I/O address is set automatically 
and the IRQ is set by the motherboard, the ports 
share one IRQ. Drivers are provided for Win 95/98 
and Win NT4.x/5.x. An adapter cable with four DB25F 
connectors is included. 

Cat. 2616 

1 Port RS232 16550 PnP PCI 


Cat. 2617 

2 Port RS232 16550 PnP PCI 


Cat. 2656 

4 Port RS232 16650 PnP PCI 


Cat. 2657 

8 Port RS232 16650 PnP PCI 


4 Port USB Hub 

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A self powered USB hub that 
has one up-stream port & four 
down-stream ports. It supports 
both full speed (12M bps) and 
low speed (1.5M bps) devices & 
is compatible with the USB 1.0 
Specification. It also supports both self-powered & 
bus-powered modes. It has overcurrent detection & 
power ready LEDs for each port. 

Cat. 2628 USB Hub 4 Port $169 

10/100Mbps Ethernet Cards 

Able to auto sense either lOMbs or lOOMbs 
operation, this PnP PCI Ethernet card uses the Bus 
Master architecture to maximise throughput. 

Cat. 11282 Ethernet Card PCI UTP/STP10/100Mbps $59 

Cat. 11272 Ethernet Card ISA BNC/UTP PnP Jmp $39 

Serial to Fibre Optic Converter 

The fibre optic converter allows 
serial input signals to be convert¬ 
ed to fibre optic signals for long 
distance, high speed and high 
quality communication. There 
are 3 LED indicators which cor¬ 
respond to RxD, CTS and power signals. 

Cat. 15074 RS422/485 to Fibre Optic Converter $499 

Cat. 15073 RS232 to Fibre Optic Converter $499 

100Mbps Ethernet 5 Port Hub Card 

Mounts on the back plane of a computer but does not 
plug into a slot, it only connects to the power supply. No 
separate case and power supply means reduced costs, 
plus everything is kept neat & tidy inside the computer. 
Cat. 11294 Ethernet Hub Card 5 Port UTP 100Mbps $259 
Cat. 11287 Ethernet Hub Card 5 Port UTP 10Mbps $99 

10Mbps Ethernet 5 Port Hub & LAN Card 

Internal PCI Plug & Play 5 Port hub and LAN card does 
not require external power supply and is a cost effective 
solution for SOHO users. One port can be used as an 
uplink port for easy expansion, or used for hub connec¬ 
tivity at the server. 

Cat. 11295 Ethernet Hub & LAN Card 5 Port UTP 10Mb $109 

Active Noise Cancellation 

Active Noise Cancelling 
Technology cancels background 
noise before it’s recorded. A must 
for Speech Recognition. In fact, 
most speech recognition software 
programs bundle a passive noise 
cancellation microphone. Active 
is even more effective. It’s also better for Internet 
Telephony & Interactive Gaming. 

Cat. 3377 Headset / Desktop - Ear & Mic ANC100 $72 

Cat. 3379 Headset - Ear (Either) & Mic ANC500 $78 

Cat. 3380 Headset - Ear & Mic (Stereo) ANC550 $110 

Cat. 3381 Headset - Ear & Mic (Disconnect) ANC600 $125 


Turn your handheld PC into a powerful data collection 
terminal. Plug the card into your handheld PC (H/PC), 
launch keyboard emulation software and you can use 
the pen-like contact scanner wand to copy bar code 
data directly into any Windows CE program. 

Cat. 8672 PCMCIA Bar Code Wand $1015 

100 Mbps Network Starter Kit 

This SOHO Network Starter Kit contains two 
10/100Mbps PCI Ethernet cards, one 4 Port 
100BaseTX hub, two 5 metre cables & detailed 
installation manual. 

Cat. 11900 Network Starter Kit $349 

Year 2000 BIOS Card 

Even Pentium motherboards 
are not immune to the Year 
2000 bug! The Year 2000 
BIOS Card solves the problem 
of progression from 1999 to 
2000 as well as 21st century leap years. It is an 8-bit 
card which provides year 2000 support for mother¬ 
boards with a BIOS which only stores the year with 
two digits, i.e. 97 instead of 1997. 

Cat. 3359 Year 2000 BIOS Card $129 

“Buddy”- Two Users - One PC 

Add a second user to your PC. 

Two users can now concur¬ 
rently access one PC. Even 
share one modem & one ISP 
account! Total Cost of 
Ownership is much lower & 
more cost-effective. 

Cat. 11639 VGA PC Share Simultaneously Buddy $599 

Bar Code Slot Reader 

An alternative to magnetic card readers (no expensive 
card writer is required). Ideal for club membership 
cards etc. A bar code is affixed to the membership 
card & the card swiped through the reader. It is a 
keyboard wedge model & the decoder is built-in. 

Cat. 8562 Bar Code Slot Reader KB Wedge $459 

Cat. 8563 Bar Code Slot Reader Serial $459 

Converter SVGA to RGB 

Allows the use of an RGB 
monitor with either VGA or 
SVGA output. It is designed 
for high resolution graphics 
monitors & has H and V synch 
signals added to the Green video channel. RGB to 
SVGA converters are also available. 

Cat. 15063 SVGA to RGB Converter $189 

Cat. 15064 RGB to SVGA Converter $194 

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Cat. 11271 Ethernet Card PCI BNC UTP/STP $39 

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Reader Info. No 10 

Moving Peop. 


with Electronics 1 

This is the first of two articles discussing the development of electronic solutions in automotive 
safety applications. As well as an insight into the actual operation of the systems, the enabling 
technologies which facilitate them will be discussed in order to give the reader an 
understanding of their complexity. In addition to the better-known systems such as ABS and 
Airbags, we’ll also be covering systems which are currently regarded as ‘niche’, along with 

advanced safety systems of the future. 

by Ross Bannatyne, 

Motorola Transportation Safety & Chassis Systems Division 

S afety systems in automobiles have 
evolved considerably in the last 100 
years. Around 1900, the round steer¬ 
ing wheel made its debut, oil and gas pow¬ 
ered lighting was replaced by electric 
lamps in 1912 and the 1920s saw the pop¬ 
ularity of much safer ‘closed’ cars, com¬ 
plete with a roof. 

The last century has also seen hydraulic 
braking systems replace crude cable or rod- 
based systems, the introduction of seat belts 
(a major safety milestone in the 50s), and 
the electronic age arrive in the 60s and 70s, 
to herald a new revolution in automotive 
safety system improvements. 

Chassis control systems 

There are several electronically controlled 
chassis systems which enhance safety by 
optimizing the interface between the tires 
and the road surface — either in the longitu¬ 
dinal, lateral or vertical directions. Fig.l 
illustrates the popular chassis control sys¬ 
tems and the associated directional dynamics 
on which they act. 

To optimize dynamic stability in the lon¬ 
gitudinal direction, there are three popular 
systems: antilock braking systems (ABS), 
four wheel drive (4WD) and traction control 
systems. Note that conventional 4WD sys¬ 
tems typically use a transfer box with vis- 

Safety features of current model Holdens 
include airbag protection for both front 
passenger and driver, activated by 
deceleration sensors. 

(Courtesy Holden Ltd.) 

cous coupling which operates when a differ¬ 
ence in the speed of rotation between front 
and rear wheels occurs. The electronically 
controlled system is more efficient, as con¬ 
siderable slip is not required before the 4WD 
operates and a better optimization of drive- 
line torsion, traction and braking capacity 
may be achieved. 

In the vertical direction, roll stabilization 
and active-suspension systems may be 
implemented, although these are still in their 
infancy in terms of the actual number of 
vehicles which include such systems. A sen¬ 
sor to detect the roll motion of the vehicle 
could also be employed in order to imple¬ 

ment a rollover protection system, enabling 
the deployment of hidden rollover bars in a 
convertible in the event of an accident. The 
same sensor could be used with the airbag 
system in order to determine when a roof 
airbag should be fired, as well as the new 
‘inflator curtain’ type airbags which protect 
occupants from glass splinters and intrusion 
during a rollover crash. 

Lateral stability is the third directional 
dynamic factor in overall vehicle chassis 
control and safety. As well as four-wheel 
steering (4WS), which increases stability 
whilst cornering at high speed, new systems 
are being introduced to compensate for 


ELECTRONICS Australia, September 1998 

Not surprisingly, Volvo’s new S80 boasts a raft of safety features, with electronics playing 
a crucial role. The company has enhanced its SIPS (Side Impact Protection System) with a 
new Inflatable Curtain, which inflates in 25ms to increase protection against head and neck 
injuries. (Courtesy Volvo Car Australia) 

understeer or oversteer by the driver. The 
industry has settled on the name ‘electronic 
stability program’ (ESP) for these systems, 
after being referred to as many names such 
as Integrated Vehicle Dynamics, Automatic 
Stability Management Systems, and others. 
ESP will be discussed later in this article. 

Taking the concepts of ESP slightly fur¬ 
ther, a fully integrated chassis control system 
would control the functions of suspension, 
steering and braking seamlessly and would 
require real-time information on all six 
degrees of freedom of the vehicle as 
well as information on the status of each 
system’s control variables and a real¬ 
time communication link with other rel¬ 
evant systems such as the powertrain. It 
is normal today for the traction control 
system to communicate to the power- 
train system in order to adjust throttle 
angle whilst applying braking forces to 
achieve optimum traction. It is expected 
that one system will control the inter¬ 
operability of all of these related sub¬ 
systems in the near future. 

Antilock braking 

The first electronically controlled safety 
feature which became mainstream was 
antilock braking systems (ABS). The 
historical significance of this system is 
notable — ABS is arguably the most 
important advancement in automotive 
braking technology since the develop¬ 
ment of hydraulic braking. 

After early mechanical implementation of 
ABS in trains and aircraft, analog-based con¬ 

trollers were implemented on several vehi¬ 
cles in Europe and the United States. The 
analog-based units however had limited per¬ 
formance capabilities, were not completely 
reliable, and were expensive. Digitally con¬ 
trolled ABS systems were adopted in the 80s 
and had excellent performance, excellent 
reliability and increasingly lower costs. A 
block diagram of an ABS Electronic Control 
Unit is shown in Fig.2. 

The block diagram is generic and it should 

Fig.1: Modern vehicles include electronic 
systems which control and stabilise 
chassis movement in all three axes. 

be noted that there is an almost infinite combi¬ 
nation of how the main functions can be parti¬ 
tioned in silicon chips. The most common 
approach is a mix between established ‘off- 
the-shelf products and custom devices such as 
advanced ASICs. In certain cases a cus¬ 
tomized silicon solution can lead to a signifi¬ 
cant competitive advantage. 

There is a clearly defined relationship 
between the slip ratio of the wheels and the 
coefficient of friction of the road surface. 
The ABS control system uses informa¬ 
tion on the wheel speeds to determine 
the slip ratio, and subsequently ensure 
that the maximum grip is applied to the 
road surface in the longitudinal direc¬ 
tion — and also that the grip is opti¬ 
mized in the lateral direction when cor¬ 
nering. An algorithm is executed in the 
microcontroller to determine slippage 
and determine how the brake pressure 
should be maintained at each wheel. 

The wheel speed sensors are still 
most commonly the variable reluc¬ 
tance type, which are robust, low cost 
and well suited for the harsh environ¬ 
ment/high temperatures at the wheel. 
But they do require considerable inter¬ 
facing. After signal conditioning, the 
stream of pulses generated by the 
wheel speed sensors are then fed into 
timer input channels on the MCU. 

A ‘fail-safe’ microcontroller, shown 
in Fig.2, is used for plausibility checks 
and to process certain parts (or some¬ 
times all of) the algorithm in parallel with the 
main micro. This is to ensure that any possi- 

A Active Suspension 
I Roll Stabilization 

4 Wheel Steering 

ESP (Electronic Stability Program) 

ELECTRONICS Australia, September 1998 


Moving People Safely 

Fig.2: Block diagram of a modern ABS (anti-lock braking system) electronic control 
unit. The serial comms interfaces are for communication with other vehicle systems. 

ble failure modes associated with the ECU 
can be determined by the system. If a failure 
mode is detected, a relay will be switched to 
disconnect the electrical system, so that the 
ABS is disabled and the conventional 
hydraulic braking (unassisted by ABS) 
remains. In this respect, the ABS system is a 
supplementary system which behaves in a 
fail-silent way should it detect any faults. A 
warning light is also switched on and often a 
fault code will be loaded into EEPROM on 
the MCU. 

It’s now common for ABS systems to 
share information with other vehicle sys¬ 
tems; hence the requirement for high speed 
serial communications. For example, the 
wheel speed information may be sent to the 
Navigation controller and the throttle pedal 
travel/position information will often be 
acquired from the powertrain controller. 

Airbag system 

The other key electronically controlled safe¬ 
ty system on today’s vehicle is the supple¬ 
mentary restraint or airbag system. Driver 
and passenger airbags are standard in almost 
all new vehicles today, with more and more 
vehicles featuring seat belt pretentioners and 
side impact airbags. The next step is ‘smart’ 
airbags which will sense occupant position 
and crash severity. These additional sensors 
will allow the system to tailor the deploy¬ 
ment using multi-stage or variable inflators 
to optimize occupant protection under a 
wider range of conditions. 

Because of the growth in the number of 
actuators and sensors for smart airbag sys¬ 
tems, a distributed airbag system has been 
proposed which uses a common chipset and 

communications technology, allowing mul¬ 
tiple airbags to be connected to the system 
easily. The key driver in the development of 
this system was robustness and reducing the 
cost. The standard components and inter¬ 
faces allow expandability, flexibility and 
reduce the airbag system suppliers time-to- 
market. The distributed airbag concept is 
shown in Fig.3. 

The system is composed of bus systems 
which allow easy integration of a number of 
airbags, switches, sensors or belt tensioners. 
The buses have been optimized specifically 

for the airbag application. The electronic 
control unit in the middle of the diagram 
includes an MCU for processing the crash 
detection algorithm, an accelerometer for 
detection of a crash and a ‘safing’ sensor. 

The safing sensor provides redundancy for 
added safety, just as the redundant micro¬ 
controller in the ABS system performs a 
‘fail-safe’ function. The safing sensor is con¬ 
nected with the firing circuit in such a way 
that it establishes a logical AND connection. 
Any firing action of the system remains 
without effect unless the safing sensor 

How the Inflatable Curtain in Volvo’s new S80 protects against 
head and neck injuries. Sensors in the B-pillar and rear wheel 
arches inflate the curtains within 25ms of a side impact. 
(Courtesy Volvo Car Australia) 

Fig.3: Block diagram of a modern distributed airbag system, 
showing the way multiple sensors and airbags can be 
connected. Standard components and interfaces allow 
expandability and flexibility, and reduce costs. 


ELECTRONICS Australia, September 1998 

agrees with the algorithm which operates on 
the accelerometer signal. 

In addition, the system includes a power 
supply and drivers for the buses. 

Electronic Steering 

Although it could be argued that the steering 
system is not, strictly speaking, a safety sys¬ 
tem, there is no argument that it is a safety- 
critical system — and as such requires care¬ 
fully implemented electronic controls. The 
steering system will, in the future, be closely 
integrated with other chassis control func¬ 
tions such as braking and suspension con¬ 
trols, to form an overall chassis control sys¬ 
tem. For this reason, the steering system has 
been included in this article on safety elec¬ 
tronics; its electrification will one day enable 
the integrated system to steer out of trouble 

There is currently a trend towards imple¬ 
menting direct-assist electric motor steering 
systems, from the more conventional electro- 
hydraulic power steering systems. In the event 
of a system fault, the direct-assist system 
requires additional safety considerations to 
ensure that the driver must always overcome 
any motor torque required to retain control of 
the steering. In this respect, unlike the ABS 
system, the direct-assist system must be fault- 
tolerant — in the event of a failure, steerabili¬ 
ty must be maintained. For this reason, addi¬ 
tional protective elements are designed into the 
controller (typically smart diagnostics). Both 
systems are shown in Fig.4. 

Both systems have similar controller 
architectures, which include MCUs and 
power stages, although the requirements of 
theses components will differ depending on 
the motor type and its associated control 
strategy. A simple PM (permanent magnet) 
DC motor would typically be controlled by 
an average performance 8-bit MCU such as a 
Motorola M68HC11. 

Electronic stability 

The industry has now settled on the acronym 
ESP to describe the many varied systems 
which handle stability management/vehicle 
dynamics. The first step in integrated vehicle 
dynamics is to introduce lateral stability as an 
incremental feature to ABS systems. A lateral 
stability ESP system aims to counteract 
extreme understeer or oversteer situations. 
Fig.5 represents a vehicle in oversteering and 
understeering situations. To counteract over¬ 
steer by the driver, an automatically generated 
brake force is applied to the front outer wheel 
to generate an outward yaw moment. To coun¬ 
teract understeer, automatically generated 
brake forces are applied to outer front and rear 
wheels to reduce vehicle speed and generate 
an inward yaw moment. This action greatly 
enhances the lateral stability of the vehicle. 

A lateral stability ESP system can be imple¬ 
mented with several additional electronic 

Electro-hydraulic power steering system controller 

Direct-assist electric motor steering system controller 

Fig.4 (above): Block diagrams 
comparing an electro-hydraulic 
power steering system controller 
(top) with one using a direct-assist 
electric motor. 

Fig.5 (right): An electronic stability 
program (ESP) system can be used 
to improve the vehicle’s lateral 
stability, as an incremental feature 
to ABS. 

Fig.6 (below): The logical algorithm 
used in a typical EPS system. It 
can be executed by the ABS 

OverstMring Understeering 

Where does the driver want to go? 

Where is the car going? 

ELECTRONICS Australia, September 1998 


Moving People Safely 

components on top of the standard ABS elec¬ 
tronic controller. A steering wheel angle sen¬ 
sor, yaw rate sensor and lateral low-g sensor 
must be added. The algorithm (shown in 
Fig.6) is executed by the ABS microcontroller 
and the wheel speed information is already 
available as generated by the ABS system. 
Lateral stability ESP is only the first stage of 
fully integrated vehicle stability manage¬ 
ment systems which will, in the future, 
integrate together steering, braking 
and suspension functions seam¬ 
lessly whilst interacting sub¬ 
stantially in real time with 
the powertrain system. The 
next logical step will be roll 
stabilization/active-suspension and then full 
active control of the chassis system with 
respect to all six degrees of freedom. 

An example of an advanced fully integrated 
ESP system is shown in Fig.7. A redundant 
communications network is employed to 
provide fault-tolerant communications in 
linking up each individual chassis control 
system to a central computer which coordi¬ 
nates the activities of each system. Typically 
a very powerful PowerPC class of microcon¬ 
troller would be expected to be used for this 
overall control function. A communications 
link would also be used to communicate with 
other systems. 

Emergency reporting 

As the modem vehicle consists of a number 
of bus systems connecting many complex 
functions, there is a very high degree of sys¬ 
tem inter-operability available. One such 
example which enhances occupant safety is 
an automatic emergency reporting system. 
This system links the airbag system with a 
wireless communications system and initi¬ 
ates an emergency call in the event that an 
airbag is fired. 

An operations centre would receive the 
distress signal and the vehicle’s position 
would be determined using a navigation sys¬ 
tem typically employing GPS. Dispatch of 
appropriate emergency services can help 
avoid further emergency situations. 



Pressure J ^ 






Data hold 

Central ESP System Controller 


-w -" 



Electronic Braking 
Control System 

Electronic Steering 
Control System 

Electronic Suspension 
Control System 

Fig.7: An example of an advanced fully integrated ESP system, of the type soon to 
become available. 

Volvo’s new S80 includes no less than 18 different microcomputers, each dedicated to 
a specific function and all linked via multiplexed digital networks. The green CAN 
network runs at 125kb/s, while the red CAN network runs at 250kb/s. The remote entry 
management system uses rotating access codes and includes an electronic 
immobiliser. (Courtesy Volvo Car Australia) 

Tyre pressure monitor 

Certain ABS system suppliers have, for 
some time, offered a system which includes 
an algorithm which can detect if a tyre’s 
pressure is low. A warning lamp is typically 
illuminated to alert the driver to this condi¬ 
tion. When tyre pressure is reduced, the 
rolling radius, or distance that the tyre travels 
per revolution changes. This can be detected 
using the existing wheel speed sensors. 

The introduction of ‘run-flat’ tyres by the 
major tyre suppliers will render this algorithm 
non-operational, as when a puncture occurs 
with run-flat’s, the rolling radius will not 
change. For this reason a new system is being 
introduced to detect tyre deflation, which 
includes a pressure sensor and RF transmitter. 
The tyre pressure from each wheel is trans¬ 
mitted to the receiver, which is shared with 
the remote keyless entry (RKE) system. 

Additional information may be sent, such 
as a wheel identifier. This information can be 
used to help determine when to best rotate 
the tyres to maintain equal tread wear. 

An example circuit used for tyre pressure 
monitor applications is shown in Fig.8. The 
module is attached to the tyre valve or may 
be molded into the tyre wall. A 3V battery 
would typically be used to provide power, 
although the system would be used in 
‘sleep’ mode most of the time, only waking 
up every 30 seconds or so to transmit tyre 
pressure. FM modulation with a carrier fre¬ 
quency of approximately 300MHz is used 
for these systems. 

In the second of these articles we’ll look at 
systems for occupant sensing, brake assis¬ 
tance, collision warning and avoidance, and 
also at anticipated future trends in auto safe¬ 
ty technology. 

(To be continued.) ❖ 



Fig.8: Block diagram for a tyre 
pressure monitor, which can be built 
into each wheel. 

Class C 

Body ITS 


ELECTRONICS Australia, September 1998 

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Conducted by Jim Rowe 

Ionospheric research isn’t new — 
and timebase correctors that ain’t! 

Let’s have a break this month from such things as ‘alternative electrotherapy’ 
devices and EM radiation worries from cellphones, and look at a couple of other 
topics that have produced interesting reader feedback. One is Tom Moffat’s article 
in the May issue about the US military’s HAARP project; the other my own review of 
a video mixer in the April issue... 

I don’t know about you, but my impression 
is that we’ve probably chewed around the 
topic of alternative electrotherapies more 
than enough — for the time being, at least. 
After a while you start going over the same 
ground again, don’t you? It starts getting 
tedious, and there’s little point to be served 
because no one is likely to change their 
views once the tedium factor comes in... 

Instead I’d thought about revisiting the 
subject of possible health risks from cell¬ 
phones, as I’ve seen some interesting discus¬ 
sions on the internet. But here again there 
isn’t a great deal of really new information; 
mainly new ways of looking at things, and an 
interesting courtcase or two. 

On the other hand a couple of letters have 
turned up on quite different topics, both aris¬ 
ing from articles we’ve published in recent 
issues of the magazine. So bearing in mind 
that the original idea of Forum was to allow 
readers to ‘have their say’ in an extended 
sense, reacting to things we publish, I’ve 
decided that we’ll look at these instead. I 
feel sure you’ll find both letters as interest¬ 
ing as I did. 

The first letter comes from Mr John 
Cameron, of Roseville in NSW. Mr Cameron 
is responding to Tom Moffat’s feature article 
on the US military’s HAARP project, which 
we ran in the May issue. Here’s what he has 
to say: 

I was interested to read Tom Moffat’s arti¬ 
cle on the US HAARP project in the May edi¬ 
tion. It brought back memories of my student 
days at the University of New England 
(UNE) in northern New South Wales. I 
thought that your readers may be interested 
to know that sites like HAARP have run in 
Australia in the past, and they are not as 
unusual as Tom implied. 

The University of New England (UNE) is 
located at Armidale, a sheep grazing area in 
New South Wales, about 500 kilometres 
north of Sydney. For a number of years from 
the late 1960s the University Physics depart¬ 
ment operated an ionospheric research pro¬ 
ject involving a very large transmitter 

designed to put energy into the ionosphere. 
Like HAARP the funding for the project 
came largely from the US Department of 
Defense, something that was not advertised 
in the University environment of the early 
1970s. I was involved with the project for a 
time in 1973. 

The main difference between the 
University of New England facility and the 
HAARP project is that the university trans¬ 
mitter beam was not steerable and ran at a 
fixed frequency. We had a single large trans¬ 
mitter and antenna rather than a number of 
smaller units. 

The transmitters, antenna and a small 
number of equipment buildings were located 
in a rural area about 10km from the 
University. If my memory serves me correct¬ 
ly the main transmitter was rated at well 
over a megawatt in continuous operation 
with a pulse power of 2 - 3MW. The trans¬ 
mitter was powered by its own 66,000 volt 
feed from the NSW electrical grid. We were 
one of the few private buyers of high voltage 
power in NSW. 

Metre-tall valves... 

While the main transmitter was simple in 
design, everything about the transmitter was 
large. It looked like a normal transmitter 
built using giant components. Most of it was 
constructed in a metal lined room. Coils 
were adjusted using mechanical linkages 
from outside the room. The transmitter 
valves stood close to a metre tall. 

The antenna was equally large, covering a 
number of hectares on tall wooden poles 
over a very large copper ground mat. The 
antenna directed the transmitter energy 
straight up to the ionosphere. I seem to 
recall the antenna had a gain of over 30dB. 

One big difficulty with using the transmit¬ 
ter was that it ran in the middle of the broad¬ 
cast band, at a fixed frequency of just over 
1.5MHz. As this single transmitter was prob¬ 
ably equal in power to the total of all com¬ 
mercial broadcast band transmitters in 
Australia, there were naturally a few restric¬ 

tions on transmitting. The main transmitter 
could only be run from midnight to dawn, but 
as a tradeoff we had exclusive use of a nar¬ 
row range of broadcast frequencies during 
the early dawn hours. 

Now you may wonder why megawatt trans¬ 
mitters are needed to research the ionos¬ 
phere. As you probably know the ionosphere 
is a layer around the earth between about 50 
and 800km up, that contains sufficient free 
electrons and ions to affect radio waves. 

When a radio wave travels through the 
ionosphere, it sets the electrons into oscilla¬ 
tion, and these oscillations are dampened by 
collisions between electrons and gas mole¬ 
cules. Above about 100km the collisions are 
sufficiently infrequent that for most purposes 
their effects can be ignored. This is called 
the E and F ionosphere region. In these 
regions it is possible to simply determine the 
ionosphere characteristics by obtaining 
echoes from a range of frequencies. This is 
done from the ground or satellites, with a 
device called an ionosonde sounder. 

But below about 100km the atmosphere 
effects things. This is the D region. Here the 
collision frequency of electrons with gas 
molecules becomes important. This makes 
the region much harder to study. One of the 
few available technique§Js to send high pow¬ 
ered pulses at between 1.5 and about 6MHz 
into the D region. This energy excites elec¬ 
trons in the D region. By studying how long 
this excited area takes to return to normal it 
is possible to understand what is occurring. 

The UNE transmitter was used to send 
megawatt pulses at just over 1.5MHz into 
the D region. Each pulse accelerated elec¬ 
trons, which then cooled as they collided 
with the tenuous gases in the ionosphere. By 
sending very short probing pulses from 
smaller transmitters through the heated 
area and studying the echoes, it was possi¬ 
ble to determine how slowly the pulse 
decayed at various heights. For example it 
was possible to analyse the effect of sunrise 
on the D region and the resulting major 
changes in radio propagation. 


ELECTRONICS Australia, September 1998 


in -me iSfco's ■••• 

The smaller probing transmitters used to 
investigate the decay of the main transmitter 
pulses were 10 - 20kW transmitters operat¬ 
ing at about 2.2MHz. These were not origi¬ 
nally crystal locked, and on more than one 
occasion there were friendly calls from the 
PMG's Department about an 'unknown 
transmitter ' wandering into the 2.182MHz 
marine distress frequency and setting off 
alarms on ships all along Eastern Australia. 

Thus HA ARP is not exceptionally power¬ 
ful by the standards of ionospheric research. 
HA ARP will ultimately run at about 3.5 
megawatts and this is not much higher in 
power than equipment we had in Universities 
here in Australia 25 years ago. 

It is possible to guess at how HAARP will 
be used without resorting to Death Star' 

Locating HAARP in Alaska is very inter¬ 
esting. It is very important scientifically, as 
in those regions one can see the conse¬ 
quences of the interaction of the upper 
atmosphere with energetic particles ejected 
from the sun (the 'solar wind') and the 
earth's magnetic field. Part of the energy 
received from the sun in that manner leads to 
the production of the Aurora Borealis. Part 
of the energy also goes into large electrical 
currents flowing in the upper atmosphere at 
an altitude of about 100km. These currents 
are strong enough and impulsive enough to 
disturb the magnetic field near the ground 

and to induce ground currents that can be 
sufficiently intense to seriously disrupt 
ground electrical networks. Currents can 
exceed a million amps, spread across a belt 
100km wide. The upper atmosphere at the 
poles is a very interesting place. 

The one original part of the HAARP 
research program is to investigate if this cur¬ 
rent can be modulated at 30 kilohertz or less, 
to generate a small low frequency signal It 
appears theoretically possible to heat elec¬ 
trons in part of the ionosphere to change the 
upper atmosphere currents by about one part 
in a million. This would be enough to gener¬ 
ate a measurable signal on the ground. 

At present the US Navy uses two low fre¬ 
quency transmitters in the US to cover the 
world. Perhaps this is a simpler way to gen¬ 
erate Extremely Low Frequency (ELF) sig¬ 
nals. For more information see the Internet 

Other claims made 

Tom's article mentioned that ‘according to 
people who have sighted HAARP internal 
documents, it's planned to expand the pro¬ 
ject until it can produce a beam of 
1700MW’. I find this highly unlikely, for 
quite a number of reasons. 

Unfortunately Tom does not state where 
this information came from. There may be a 
simpler explanation, as 1700MW would seem 
to be about the theoretical isotropic power of 

the HAARP transmitter. When discussing 
heating and other effects, sometimes the 
transmitter power level is quoted as if the 
transmitter radiated equally in all directions. 
A torch beam compared to a point source of 
light illuminating the inside of a globe uni¬ 
formly would be a visual analogy. The ulti¬ 
mate HAARP transmitter power of 3.5 
megawatts with the antenna gain of about 
500 (say 25-30dB) would be equivalent to an 
isotropic transmitter of 1700MW. Possibly 
the theoretical isotropic power level has been 
given in some document and someone has 
confused it with the transmitted beam power. 

The other claims by Tom in the article 
need rather more backup before they could 
be seriously considered. I like Tom's writing 
style, but he needs to stop writing specula¬ 
tion as if it was fact. I have always believed 
that the more unusual and extreme the claim 
the greater the need for evidence. But Tom 
does not produce any evidence. 

For example he comments on a Russian 
transmitter (Woodpecker) that 'many scien¬ 
tists feel that the woodpecker's real purpose 
was to experiment with modifying human 
brain function'. Now this is a really major 
thing to claim without any supporting 
sources. He needs to start naming his 
sources if he wants to be taken seriously 
rather than comments such as 'other docu¬ 
ments come from sources we'd rather not 
know about ’. 

ELECTRONICS Australia, September 1998 



1 hope you find the above comments of 

I did indeed, Mr Cameron, and I imagine 
other readers will as well. Thanks for 
describing the ionospheric research setup 
near Armidale in the early 1970s, and help¬ 
ing to put the HAARP project into clearer 
perspective. Your point that ‘solar wind’ par¬ 
ticles from the sun can already produce cur¬ 
rents of millions of amps certainly suggests 
that the excitation produced by HAARP is 
still rather short of the level needed to 
destroy the planet, doesn’t it? 

I take your point that our ‘Death Star’ 
wording in the heading and on the cover was 
probably a bit ‘over the top’, but we niche- 
market magazines tend to get Tost in the 
noise’ nowadays unless we attract attention. 
Hopefully the wording did that, at least. 

TBC, or synchroniser? 

Moving on, our second letter is in response 
to the review I did in the April issue, of the 
Video Tech VMX400 Video Mixer and 
Timebase Corrector. Our correspondent is 
Mr Gary Yates, of Frenchs Forest in NSW, 
and although he doesn’t say as much I sus¬ 
pect he’s actually the father of our frequent 
contributor Darren Yates. Basically he’s 
writing to question the use of the term Time 
Base Corrector, by both Video Tech and 
myself, in connection with the circuitry in 
devices like the VMX400: 

Forgive the familiarity, but I feel I know 
you. I’ve been reading EA/RTV&H since 
1958 and was initiated into electronics via its 
excellent articles and construction projects. 

I’ve just read the April 98 edition (yes, I’m 
a bit behind) and came across your review of 
the Video Tech VMX400 vision mixer. From 
the article I got the impression this unit is 
meant to be used with domestic VCRs. The 
following letter is based on this assumption. 

Liberally sprinkled through the review are 
the capital letters TBC, which of course 
stand for Time Base Corrector. I would like 
to throw a cat amongst the pigeons and say, 
from the description of the device, it is not a 
TBC but a Video Synchroniser (VS). These 
are two different devices, as follows: 

LA VS is a freestanding device and a TBC 
is not. 

2. A VS requires a 625 TV line memory. A 
TBC only needs a 20 TV line memory. 

3. A TBC outputs a fault-free video signal, 
while a VS does not. 

Just to recap, a little bit of tape recorder 
theory. Any tape recorder, be it video or 
audio, if it is to work well, must maintain its 
tape speed accurately. Usually tape 
machines have two speed problems: 

1. Dynamic speed variation, called Wow & 
Flutter ’ on audio tape machines. 

2. Static speed offset error, which causes 
tone pitch shift on audio machines. 

A TBC works to correct these in video 
machines as follows. 

The usual method to fix dynamic speed 
variation on the video output of a VCR is to 
feed the VCR output into a memory unit, with 
the input, clock locked to the VCR output and 
clock it out at a fixed rate locked to a refer¬ 
ence signal input. The dynamic errors in 
most video machines are usually less than 
+/-10 TV lines and hence only a 20 TV line 
memory is necessary. The output is effective¬ 
ly tapped halfway down the memory so that 
it can increase or decrease the signal delay 
by up to 10 TV lines. 

As you can probably guess, a small 20 TV 
line memory is not going to handle a static 
speed error, which will need an ever increas¬ 
ing or decreasing time delay correction. To 
solve this problem a DC control signal is 
derived from the 20 TV line memory address¬ 
ing circuitry, so that: 

1. At 10 TV line delay the DC output voltage 
is zero. 

2. At 20 TV line delay the DC output voltage 
is positive. 

3. At zero TV line delay the DC output volt¬ 
age is negative. 

The DC output signal swings smoothly 
between these limits depending on the aver¬ 
age time delay. This DC signal is fed back to 
the capstan speed servo in the VCR, to speed 
up or slow down the tape to remove the stat¬ 
ic speed offset and keep the average speed of 
the VCR video output signal exactly match¬ 
ing the reference signal fed into the TBC. 
There will thus be no time errors on the 
video output of the TBC. 

Now let's turn to the video synchroniser. A 
VS relies on the fact that the video signal vir¬ 
tually repeats itself every 625 TV lines. 

Domestic VCRs do not have any external 
inputs to their capstan servo circuitry. Due 
to the relaxed tolerances of these servos, it’s 
a good bet they will also have a static speed 
error to a certain degree and this will get 
worse as the VCR ages. 

Let us assume that the VCR speed is a lit¬ 
tle fast (a positive static speed offset) and, at 
this point in time, the start of line 1 of the 
VCR video output is coincident with the same 
point on the reference signal fed to the other 
input of the VS. 

At the end of line 1 the VCR signal synch 
pulse will occur before the synch pulse of the 
reference signal. (Because the VCR is run¬ 
ning fast, the line synch pulse frequency will 
be higher and the time between the synch 
pulses will be shorter.) The 625 TV line 
memory will add a slight delay to the VCR 
video signal, to make sure its synch pulse is 
coincident with the reference sync pulse. 

At the end of line 2 the memory will add a 
little more delay again to get both the second 
synch pulses to line up, and so on right 
through the 625 TV lines in the frame. (Of 

course the memory is actually adding tiny 
amounts of delay right through each line; not 
just one big jump at the end of each line.) 

So you can see the memory is adding more 
and more delay, until it hits the end stop and 
there is no more memory left. The VS over¬ 
comes this problem by simply snapping back 
to zero delay and starting all over again. 
This gives an apparent synchronous output, 
BUT what actually happened was that the 
memory dropped a whole frame of video. 
Discarded it. Threw it away. Never to be 
seen again. What does this really mean? 

Well, if the VCR is running fast, the pic¬ 
ture will jump forward (skip a frame) every 
so often — or if the VCR is running slow, the 
picture will jump back (repeat a frame) 
every so often. These jumps will give you a 
rhythmically jerky picture. Flow often 
depends on how far out the speed of your 
VCR is. The greater the speed error, the 
more often the jerk. 

Some advanced video synchronisers get 
around this problem by having a Rolling 
Frameline Update system. Instead of adding 
or skipping one complete frame every 100 
frames (for example), they just add or skip 
one hundredth of a frame (6.25 TV lines) 
every frame. This produces a different fault 
on the picture. A scene change can occur 
partway down the frame. The previous scene 
would be in the top part of the frame and the 
next scene would be in the lower part. The 
picture update line will cycle through the 
frame continuously, but you will only see it 
when the scene changes. 

A TBC does not produce either of the 
above faults and is, in my mind, the better 
unit. Unfortunatly, it cannot work with 
domestic VCRs. 

It would appear that the Video Tech 
VMX400 is not a TBC and therefore there is 
the chance it will produce picture errors if 
your domestic VCR has a static speed error. 

Thanks indeed for that explanation and 
clarification, Gary. I confess I did half¬ 
remember the correct terminology and the 
distinction between a TBC and a video syn¬ 
chroniser when I was writing the review, but 
used the term ‘TBC’ because Video Tech 
and the other manufacturers seem to use it. 

I suspect you’re quite correct that the 
devices are really video synchronisers, and 
would therefore be capable of producing the 
kind of picture errors you describe. All I can 
say, though, is that during my testing of the 
VMX400 — with a couple of different 
domestic VCRs, one quite elderly — I really 
didn’t notice any errors of this type. 

I had assumed that the memory in the 
VMX400 was organised like a big FIFO 
buffer, where the addressing simply goes 
‘around and around’, and both the writing 
and reading were on a line-by-line basis so 
there wouldn’t be any sudden jumps on the 
output. Are you sure they couldn’t be doing 
things along these lines? 

But that’s about all we have space for this 
month. Cheers! ♦> 


ELECTRONICS Australia, September 1998 

Now Books 

Cosmic ray saga 

COSMIC BULLETS, by Roger Clay and BOiJfcR 11 ay 
Bruce Dawson. Published by Allen & & HMUCfl davvson 

Unwin, 1997. Soft covers, 198 x 131mm, 194 
pages. ISBN 1-86448-204-4. RRP $16.95. 

Another title in the Allen & Unwin 
‘Frontiers of Science’ series edited by 
Professor Paul Davies of the University of 
Adelaide, designed to describe current 
research and developments in selected topics, 
in an accessible way. The authors of this vol¬ 
ume are also at the Uni of Adelaide, as 
research physicists, and are experts in cosmic ray research. 

In Cosmic Bullets they explain that despite a fair amount of work 
over the last century or so investigating cosmic rays, there’s still a lot 
about them that isn’t properly understood — like where many of them 
come from, and the exact mechanisms whereby such high energy par¬ 
ticles are created in the first place. The aim here is to give the reader 
a good understanding of what has been achieved to date in studying 
these intriguing ultra-high energy particles, what they’ve told us so 
far, and what the challenges are for current and future research. 

For anyone with a reasonable background in science (which prob¬ 
ably includes most readers of EA, I imagine), it should make very 
interesting and accessible reading. The authors start with a rundown 
of basic particle physics, and follow this up with a narrative of what 
has been found over the last century. This then gives you a good foun¬ 
dation to understand and appreciate their description of current 
research projects and where they’re heading. 

As cosmic ray research is closely allied with electronics, I imagine 
many of our readers will find it as interesting as I did. There’s both a 
glossary and a bibliography at the end, by the way. 

The review copy came from Allen & Unwin, of 9 Atchison Street, 
St Leonards 2065. (J.R.) 

Learning electronics 

ISTS, by Stan Gibilsco. Published 
by Tab Books, 1997. Hard cover, 

194 x 242mm, 961 pages. ISBN 0- 
07-024190-2. RRP $150. 

This book is the largest I’ve seen 
from this prolific author, which 
helps explain its rather high price 
tag. It claims to cover virtually every 
aspect of hobby and consumer elec¬ 
tronics, and it certainly covers a lot 
of ground. There are some formulae 
given, but for the most part things are kept relatively simple. To me, 
the book could be improved with more tables, equations and circuits, 
and less text. 

Being an encyclopedia, all entries are in alphabetical order. 
However, there’s also an index which helps you find subtopics with¬ 
in an entry. The main problem is what it leaves out. The content is 
very general, and broadly covers most aspects of electronics, includ¬ 
ing a few that seem irrelevant. For example, nearly a page is devoted 
to the term ‘Luddite’... 

As you’d expect, computers and their peripherals get a lot of cov¬ 
erage, as does radio, television and other consumer appliances. The 
book is ideal for browsing, and would certainly give a non-technical 
person or a beginner to electronics a good idea of electronic equip¬ 
ment and appliances. But it is not a reference book for technicians. 

The review copy came from McGraw-Hill, PO Box 239, Roseville 
2069. (P.P.) ❖ 



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ELECTRONICS Australia, September 1998 



> • • 


The customer who’d imported what was 
very nearly an expensive boat anchor! 

Paying to have a piece of 
very expensive second¬ 
hand electronics equipment 
shipped from the other 
side of the world can be 
pretty risky — especially 
when the equipment 
concerned is a high-end 
valve hifi amplifier, as one 
of this month’s stories 
illustrates. We also have 
the tale of tracking down 
weird intermittent faults in 
an ageing germanium-era 
electronic organ... 

T his month we open the column with a 
story from a familiar contributor over 
the Tasman, Peter Lankshear. You’ll no 
doubt recall that Peter conducted our 
Vintage Radio column for many years and 
from that you might deduct (correctly) that 
he is a ‘full bottle’ on valve technology. This 
story continues his association with the old 
‘bottles with lights in them’, although this 
equipment is more up-market than the old 
five-valve mantels he used to write about. 
Here’s what Peter has to say... 

This story is unusual in that it describes a 
repair job that started in England and was 
completed 20,000km away, in New Zealand. 
It also made me aware of the questionable 
ethics of the service persons concerned. 

An unforeseen and remarkable develop¬ 
ment in the ever-changing world of electron¬ 
ics has been the widespread enthusiasm dis¬ 
played by a significant number of audiophiles 
for perpetuating the use of valve audio ampli¬ 
fiers. The outcome has been the manufacture 
of expensive and technically obsolete equip¬ 
ment and at times an acceptance of what are, 
in fact, reduced performance standards. 

A related group of enthusiasts has gone to 
great lengths to search out and have refur¬ 
bished, surviving classic high quality ampli- 
Jiers such as the Williamson, Leak and Quad. 
Unlike some present day valve counterparts, 

these do have high performance figures. 

During the 1960s, one of the last of these 
classics to appear was the Radford, a 'no 
compromise ’ example of the best of valve 
technology, with a specification that even by 
today’s standards is impressive. Capable of a 
genuine 100 watts RMS per channel at 0.1% 
distortion , its two output stages each used a 
pair of ultralinear connected KT88 tetrodes. 

The phase inverter driver stages were 
long-tailed pairs of frame grid EF184 TV 
pentodes and the input stages used cascode 
ECC88 double triodes. The complete stereo 
amplifier is quite large, massive and very 
heavy. To lift one entails first taking a deep 
breath and then risking a hernia! 

One local enthusiast was so keen to 
obtain one of these monsters that he 
arranged the purchase of one in England 
and had it air freighted to New Zealand. 
What his freight bill totalled, 1 hate to think. 

By all accounts, the amplifier had been 
used in a pub. That it was working at all is 
more a tribute to Radford quality than to its 
environment, but the new owner soon dis¬ 
covered that whilst one channel seemed to 
be operating well enough, the other was not. 
A new set of very expensive valves did not 
help, and it was then that my aid was sought. 
/ agreed to look it over and the monster was 
duly heaved onto my workbench. 

Upended and with the bottom cover plate 
removed, some serious modifications were 
immediately apparent. The output stage of 
the faulty channel had been altered to more 
or less straight tetrode operation, with 
reduced screen and altered bias voltages. 

This suggested that a misguided attempt 
had been made to change the operating 
conditions to class AB2 — not possible with 
conventional driver coupling. This roused 
some deep suspicions. It is not unknown for 

The Radford STA-25 valve power amp, ‘little brother ’ of the model discussed in Peter 
Lankshear's story. 


ELECTRONICS Australia, September 1998 

a circuit to be modified in a vain attempt to 
cure a fault, but such desperate measures in 
this type of equipment never work. 

At this stage, with no data or circuit avail¬ 
able, I was not prepared to do any more 
until some information could be obtained. 

The required manual eventually arrived, 
and I was able to check all components like¬ 
ly to have deteriorated, and restore the cir¬ 
cuit to its original state. Most resistors and 
capacitors were mounted on printed circuit 
component boards with numerous connec¬ 
tions to the valve sockets and power supplies. 

A methodical progress through the ampli¬ 
fier revealed only a few components out of 
close specification, and most of the work 
entailed tidying the wiring, replacing 
butchered terminals and sockets and cor¬ 
recting the modifications. Because I had 
found no really faulty capacitors or resis¬ 
tors, I was had an open mind as to whether 
or not the crippled channel would now work. 

One hand in pocket... 

With the amplifier switched on I took a 
detailed set of meter readings and found that 
the voltages of both channels were close to 
specification. (With 600 volts of HTfloating 
around the chassis, I made sure one hand 
was firmly in my pocket!) So far so good. It 
was now time to listen to the audio quality. 

To connect a 100-watt amplifier directly 
into a workshop speaker is a bit pointless and 
potentially damaging, so I fitted up an 8Q high 
wattage load resistor with a small sample of 
the output for the speaker. With an FM tuner 
connected and the gain wound well up, both 
channels produced what seemed to be plenty 
of high quality output. Certainly, the horrible 
sound from the modified stage had gone. I sat 
back, enjoyed the music and speculated as to 
the real reason for the modifications. 

There was however still a lingering 
doubt, so I dusted off the oscilloscope, an 
audio oscillator and a meter known to be 
accurate at audio frequencies and set about 
measuring the output. The good channel 
produced a fraction over the required 28.3 
volts into 8 ohms, but the other managed 
only half of this figure, equal to 25 watts. 
This confirmed (a) the futility of using ears 
to measure audio levels, and (b) that there 
was still a fault. 

What was left to go wrong? It had to be the 
output transformer. Swapping the connec¬ 
tions over to the good channel confirmed 
that there was indeed one Jaulty transformer. 
It was the worst possible fault — and the 
most expensive item by far, assuming a spare 
could be found, which was unlikely. 

Here was the real reason for the modifi¬ 
cations. Someone had probably discovered 
the faulty transformer and had attempted to 
correct the lack of output by altering the 
output stage. And when this was unsuccess¬ 
ful, the owner must have decided to quit the 
amplifier. I couldn 7 help but wonder if it 
would have been exported to New Zealand 
had it been in good condition... 

A 100W wide range output transformer is 
a massive beast. It has about twice the 
amount of iron required for a power trans¬ 
former of the same power rating and is at 
least twice the size of the mains transformer 
for a large valve receiver. But the real 
problem is the very specialised sectional 
winding methods. The Radford transformer 
has four secondary and four primary wind¬ 
ings and each primary section is tapped for 
the ultra linear screen connections. 

Furthermore, two of the primaries are 
wound in the reverse direction and as each 
pair is connected in parallel, the number of 
turns on each section has to be exactly the 
same (in this instance WOO turns). If the 
transformer could not be repaired or 
replaced, there would be an unhappy owner 
of a very expensive boat anchor. 

Valve amplifier enthusiasts are purists, 
and only a Radford transformer would have 
really been acceptable. 

There was one possible solution. New 
Zealand Vintage Radio Society members 
are fortunate in that one of their number is 
a REAL transformer rewinding expert. He 
has been at the game for over 60 years and 
will tackle anything, invariably turning out 
a superb job with better craftsmanship and 
materials than the original. 

He also has an extensive database of trans¬ 
former specifications and when he is con¬ 
fronted with a new transformer, his first 
action is to meticulously unwind it, noting the 
exact number of turns and the configuration. 
But would he take on the complex Radford? A 
phone call ascertained that he would! 

The beautifully rewound transformer 
duly arrived back and was soon in opera¬ 
tion with full output now available on both 
channels. One very happy owner was able 
at long last to enjoy his music, and I was 
able to reflect on the perils and expenses of 
repairing old amplifiers, and the inadvis¬ 
ability of importing used equipment. 

However, there was one last sting in the 
Radford’s tail. A few weeks later the owner 
called to say that he now had a small annoy¬ 
ance. He listened in rapture to the Radford 
daily, but about once a week it would briefly 
produce a small frying sound that would dis¬ 
appear as soon as the occupant of one par¬ 
ticular EF184 socket was touched. 

He had tried several new valves to no 
avail. A fter all we had gone through, to now 
have an intermittent fault was as welcome 
as the proverbial hole in the head! 

There was nothing for it but to invert the 
chassis on the workbench and leave it run¬ 
ning. Nothing happened for a few days. I 
felt it was a dry joint of some sort and even¬ 
tually resorted to prodding around. Here 1 
found that one section of the PC board was 
at times microphonic. 

Out came the board — again — but a 
close inspection with a magnifying glass 
showed nothing unusual. I then unsol¬ 
dered one of the joints in the troublesome 
area, to discover that the resistor lead 

was quite black under the solder. 

This had to be the problem and although 
externally they appeared OK, several simi¬ 
lar joints were found. To make completely 
sure I unsoldered all the component leads, 
cleaned and then carefully resoldered them. 
This was a year ago and the Radford has 
not given any further trouble. 

If a conclusion can be drawn from this 
adventure, it is that all equipment has a 
finite life — which can be extended, but 
often with considerable and uneconomic 
effort. I believe it also shows why it is 
unwise to import used equipment without 
some safeguards. 

So how about that? I wonder what would 
have happened if the Transformer Whizz 
had been unable or unwilling to tackle the 
rewinding job. As you say, Peter, it would 
have been a very expensive boat anchor... 

Of course, we don’t know the history of 
the amplifier. The modifications may have 
been authorised by an owner who was quite 
satisfied with the compromised perfor¬ 
mance. I’ve struck people who are happy to 
have quite expensive gear patched up rather 
than properly repaired. 

The argument often is that they aren’t suf¬ 
ficiently interested in high quality to warrant 
the extra cost of full repairs. And I suppose 
the attitude is quite legitimate. But then, why 
did they go to the expense of buying costly 
gear in the first place, if quality wasn’t impor¬ 
tant? Did they only buy the brand name? 

The practice of Tough patching’ only 
becomes unethical when the equipment is 
sold off and the new owner is not told of the 
service history. It’s not often possible to 
conduct full output trials on high-end audio 
products, and low level tests can be quite 
misleading. I imagine that’s what has hap¬ 
pened in this story. 

Thanks for that tale, Peter, and we are 
looking forward to your next contribution, 
whenever it may be. 


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ELECTRONICS Australia, September 1998 




Hammond organ 

And now for a story from another frequent 
contributor. He is Robert Abel, from 
Condobolin in NSW. This time Robert has 
written about a subject that seems to be 
much more common these days than in the 
past. Here’s what he has to say... 

After the last couple of jobs which were 
mostly mechanical, this one was a genuine 
electronics fault. But after a reel to reel 
tape recorder and a VCR, what else could I 
get involved with but an electric organ? 

The organ in question is a Hammond, 
with two 44-key manuals and 13 foot pedals, 
and I quote from the service notes: 'The 
Upper Manual contains three sixteen-foot 
voices, Flute, String and Reed. The Lower 
Manual has two 8 ’ stops, Tibia and Cello. 
With the addition of Reverb, Manual 
Balance, Vibrato I and II, and Pedal Accent, 
the VS 100 is a simple but functional organ ’. 

Note that VS 100! This particular organ is 
a V222, an earlier model with exactly the 
same features but using discrete transistors 
(germanium 2SB56s), where the VS 100 uses 
a simple IC (LD3061) to do the same jobs. 

There is a 'Generator ’ board containing 
12 oscillators (the top octave) ranging from 
554Hz to 1047Hz and these, of course, run 
continuously when the organ is switched 
on. Other notes are derived from a series of 
dividers on three separate boards, con¬ 
trolled from the key switches on the upper 
and lower manuals and the foot pedals. The 
various 'voices’ are controlled by rocker 
switches alongside the Upper Manual. 

I found that the organ had been pur¬ 
chased as a demo model in 1975, which 
also happens to be the year I decided to sit 
out my retirement(?) in this town. 

I did not become affdiated with the body 
which owned the organ until 1977, and it 
must have been shortly after that when 1 
was persuaded (compulsorily volunteered?) 
to restore some key contacts which had 
become rather uncertain and scratchy. 

Over the years since then, another peculiar 
fault developed, manifested at first by an 
inability to obtain any output from the firstfoot 
pedal (it should sound bass at around 66Hz). 

After the organ had been switched on for 
a while, brief bursts of bass would erupt 
periodically (with the pedal held down) 
until eventually the output was continuous 
again. And so, for a time the trouble was 
not regarded as serious enough to warrant 
expert attention. 

The 'warm-up ’ periods gradually became 
longer over time and then the fifth note on both 
manuals became affected, roughly doubling 
the pitch when the pedal was inoperative. So it 
became the practice to turn on the organ about 
4pm, to enable normal use in the evening. 

This might have continued indefinitely, 
except that this year, with the annual instal¬ 






Inside a Hammond VS100 electronic organ, showing the main system modules. The 
V222 is apparently very similar. 

lation looming, the organist reported sever¬ 
al notes inoperable, necessitating a repeat 
of my previous job on the key contacts. 

So, there I was, once again cleaning and 
adjusting the leaf contacts and allowing my 
curiosity to ponder the reason for the bad 
behaviour of the first pedal et al. 

I took some voltage readings along the 
(very dusty) sides of the nearest boardful of 
germanium devices (2SB56’s) and found 
that the usual result was in the region of 
12.5 volts, until suddenly I found a reading 
which refused to hold still but seemed to 
'toggle ’ between about 5 and 16-19 volts. 

This had to be the circuit I was seeking 
and to confirm it, after a session with vacu¬ 
um cleaner and a soft paintbrush, I unsol¬ 
dered leads variously numbered Ul, LI, 
and PI. These were the leads coming from 
the faulty notes on the Upper and Lower 
manuals, and the first pedal key. 

It was not an easy matter to inspect the 
underside of the board because of the restraint 
imposed by the wiring, but I located a transis¬ 
tor which had to be part of that circuit and 
took it out for testing. It was perfectly OK and 
fitting a replacement had no effect at all; the 
voltage continued to toggle as before. 

That’s when I noticed that there were two 
25B56s in this circuit and of course the sec¬ 
ond one WAS faulty, with very high leakage 
current. The toggling effect vanished with 
its removal, and after fitting a replacement 
a check showed that all three notes were 
playing normally again. 

I can’t understand why the high leakage 
current should cause the device to toggle, but 
I assume that the fact of toggling would per¬ 
haps have racked up a charge on one of the 
associated capacitors, sufficiently to stabilise 
conditions in the circuit for a time and so pro¬ 
duce a normal note until the charge dissipated. 

But this does not explain why — after an 

hour or two — normal operation would 
return! No doubt one or more of the organ 
service people who read this will put me 
right about all this... 

I wondered then about the tuning of the 
main oscillators and contacted a colleague 
who, although older even than myself, still 
runs a healthy repair shop and who I knew 
had operated on a number of Hammond 
organs and could be relied on to have the 
necessary information on frequencies, etc. 

Armed with my new knowledge and with 
trusty 1GHz Counter under arm, I took our 
organist over for a trial run. I am quite fond 
of music — though totally incapable ofpro¬ 
ducing any myself — but I wasn ’t sure 
whether to be pleased or just a little disap¬ 
pointed when the expert declared the tuning 
perfect and all / needed to do was put the 
covers back on! Oh, well, you win some... 

That was an interesting interlude, Robert. 
As you said earlier, it’s a very electronic yam 
and, on reflection, one that has meaning even 
outside the field of Hammond organs. 

There are still a lot of products about that 
use old germanium transistors and your 
description of unusual behaviour in those 
devices might help to solve problems for 
other servicemen. 

By an odd coincidence, I was sorting 
some old manuals yesterday and came 
across a service manual for the Hammond 
model VS 100, along with the installation 
manuals for a Leslie model 130 speaker and 
the 7830 control connector kit. I don’t know 
how I came to have them in my collection, 
but someone locally must have been work¬ 
ing on one of these very popular organs. 

Thanks for that story, Robert. We’ll look 
forward to more unusual tales from your 
rather active retirement. 

And that’s it for this month. There’ll be 
more next time, if the fates are willing. ❖ 


ELECTRONICS Australia, September 1998 


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Analogue/Digital Designs, Firmware, CAD Services 
and PC based Applications 
From concept to the finished product, rescue of never 
ending designs or update of existing designs. Reliable, 
Affordable and On Time Services 
Phone/Fax: (02) 9858 1085 
50 Cobham Ave, West Ryde NSW 2114 

ELECTRONICS Australia, September 1998 



m % \/ + 

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I Cc 

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RBLL Electrolytics 

See our great range of low 
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Value Working Cat. Price 
(uF) volts (V) 

50 R 4800 $0.15 

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25 R 4828 $0.30 

25 R 4830 $0.30 











Green fashing LED 

5mm, round 3.5 mcd. 


BUX80 bipolar 
power transistor 

NPN 10A switching 


SAVE $3 


1 x RCA plug to 

2 x sockets 

Gold offset angular 
audio adaptor. 




Air speed and 
temperature meter 

Handheld meter with 4 digit display for 
wind speed and temperature readings, with 
protective carry case. 

Air flow range: 0.4-30m/s, 

Temp, range -10° to 50°C, 

1 +14° to 122°F. Continuous 
moving average. 
Min/Max/Avg (single point). 
Air flow average 
for multipoints. 

Q 1411 



Digital multimeter 

3.75/4.75 digit multimeter. Fast 4000 
count display updates 5 times per 

second. 10 times high 
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display mode updates 
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Dual display mode allows 
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Fast analogue bar graph 
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resolution low frequency readings. 
Capacitance readings 
tO 40,000pF Q 1565 

SAVE $20 

$ 229 

Direct Link is equipped 
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1 jUPCl 1j|| k t0 su PP'y you with a 
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Clear cable 

Pack of 10. Suitable for 

/ \ 

7 V 

4-way filter board 

Effective protection against common 
forms of AC power disturbances, surge, 
spike and suppression. Use with 
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systems and 
in offices. 



ZapCatcher2 filter 

Filters nasty zaps from phone & power 
lines. Surge/spike protection with single- 
stage filter prevents damage from 
electrical noise. 



7 7 7 7 

PC 10 2-stage filter 

Great protection for office equipment 
and Hi-Fi systems. Indicator light goes 
out if protection circuit 
is damaged. 



6-piece precision 
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; A handy selection of flat- 
blade screwdrivers with 

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See your handiwork clearly with these 
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UB5 style 28 x 54 x 83mm 
h 2955 $4.50 ea or 





Hobby Boxes 
With Handles... 

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131 x 67 x 34mm H 2846 Was $14.95 
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160 x 80 x 44mm H 2848 Was $ 17.95 
197 x I 10 x 56mm H 2849 Was $19.95 

Ultra-bright ImW 
laser pointer 

Great for presentations with 
250 metre indoor range and 
improved brightness. 

T 2909 



| H-16?5 ~| 

Mixed Computer Screw Peck 


screw pack 

10 pieces x 6 types 
of the most 
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Pack of 60. 

B 3443 L 

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f f/rW.'f*! 

Huge selection of heatshrink tubing. 
Range of sizes to suit your needs. 


at the PowerHouse, 
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Parramatta. Hobart. 
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1.5mm x 

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16mm x 1.2m White w 4179 $24.95 
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Direct Link is equipped 
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ll Is k t0 su PP*y y° u w 'th a 

< V hassle free delivery 
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PHONE 1300 366 644 to reserve your order 


i n wni 

Velcro colour cable strap 

10 pack of 25mm x 200mm 
(re-usable) mixed colours. 

H 1948 

14 ” 

Tamiya type connectors 

Supplied with one female and 
one male end. 

M 9619 

64pc security bit set 

Packed in two soft plastic storage cases 
for easy carrying. With security Torx, 
Tri-wing, Hex and Philips bits and 
magnetic bit holder. 

T 4501 

32pc security bit set 

For use with equipment with security 
screws. Includes Torx, Hex, Tri-wing, 
pin drive, magnetised bit 
holder and soft plastic case. 

T 4506 


Wah Waih guitar pedal 9 

• Popular guitar effect is controlled by a 
foot pedal (not included), the resulting 
sound produces an effect where the 
volume suddenly increases 

then decreases. 

• Includes PCB 
and components 

• Includes instructions 
and advice on how to 
use it with your guitar 
and foot pedal. 

• Far less expensive than 
pre-built units. 

K 5620 

Sep ‘98 


$ 26 9S 

Soundcard pre-amp 9 

• Turns your PC into an audioscope or 
an audio wave-form generator 

• Switchable input ranges from 
+20dB to -40dB 

• With IM ohm input impedance and 
limit indicator 

• Power source required 5V DC 
(from sound card port) 

• Free software provided to get 
you started 

• Supplied with all components, 
hardware, PCB, case, pre-punched 
screen and front panel 



Motorcycle intercom 

• Provides 2-way communication for two 
riders on the one bike 

• Sturdy and durable, with a full 
duplex operation 

• Uses a filter to make signal clear 

• Features a single volume control for 
both channels 

• Requires 4 x AA batteries or power 
directly from motorcycle 

• Includes all components, plastic case, 
PCB, electret microphone 

and speaker for 
helmet installation 



l|o •'» 

Shorted turns tester 

• Low cost, battery operated tester for 
line-output or ‘flyback’ transformers 

• Small, rugged and a great aid for 
servicing TV receivers, video monitors 
and computer power supplies 

• Identifies faults in 
horizontal output 
stages and tests LOPTs 
in particular, for the 
presence of shorted 
winding turns 


Exclusive to Dick 
Smith Electronics 

-(g). Aug‘98 


Video fader and wiper Q Q 

• Good for home videos, allows professional 

• Fade out from one image and into the 
next, or wipe-out from one image to 
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• Built-in enhancement facility to 
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• Power source required: 12V DC 

• Supplied with all components, hardware, 
sloping case, [ . q 0 0 0 


I save $ 10 


« 69 91 

999 M 

PCB power 
adaptor, and 
pre- punched 
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K 5415 

Universal charger 

Immensely popular! 

• Designed to fast charge 
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• Also charges 6V and 12V sealed lead 
acid (SLA) packs and lead acid car and 
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• Power source required: 240VAC 

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PCB, plastic case, pre-punched and 
screened front panel and pre-punched 
rear panel 


Feb ‘98 


Great Value Was $549 NOW $399 

180Watt Stereo Amp 9991 

• Complete kit including case, heatsinks, transformer, and all components! 

• Output power: 255W (continuous), 380W (IHF - short term) into 4 ohms 

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• Harmonic Distortion: 0.005% at I00W RMS into 8 ohms I 

.Feb ‘94 

Limited Stock 


save $150 

$ 399 



B 3443 R 




100 wipes soaked in a 
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W— DSE Electrical 
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This electrical lubricant is 
great for PC boards, cameras, 
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Great value cleaner for use 
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keyboards, phones and CD 
players. 300g. 


Un-Du label remover 

Evaporates rapidly, and 
includes spade to 
* remove stickers cleanly. 
Retains sticker 

30ml bottle. 

N 1204 



Master Handbook 
of Acoustics 

B 1749 


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3rd Edition 

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Maintaining & 
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This magazine is now on sale at all of our New Zealand stores! 





$ 52*5 

|-LCD digital 

Hi-tech precision tool for 
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O 1412 


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Features 2 multi-function remote controls, 
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Pioneer GPS 

Affordable satellite 
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B 3443 R 


PHONE: 1300 366 644 (Local Call Charge) FAX: (02) 9395 1155 - U* 

MAIL: DICK SMITH ELECTRONICS, Direct Link Reply Paid 160, 

PO Box 321, North Ryde NSW 2113 (No Stamp Required) 

Please add postage (up to 5kg) to your order, as follows: 

• $4.00 Up To $50 • $7.50 $51 Up To $100 • $9.00 $101 Up To $500 • $11.00 over $500 
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•Major Credit Cards Accepted. • Gift Vouchers Available 

Not available it aH 
authorised stockists. 

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VIC Bourke St Shop 2, Basement cnr Bourke/Swanston Sts... 9639 0396 

TAS Shop U52-U56 Eastlands Shopping Centre Bligh St, Rosny Park...6244 2555 

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WA Rockingham Cnr Read St/Commodore Dve. 9592 2888 

Circuit rfl 

Design Ideas 

Interesting original circuit ideas and design tips from readers. While this material has been checked 
as far as possible for feasibility, the circuits have not been built and tested by us. We therefore 
cannot accept responsibility, enter into correspondence or provide any further information. 

Break Finder 

Simple mod improves Cable 

The Cable Break Finder published in 
February 1998 is designed to test faulty 
cables, but what it can’t tell you is whether 
the cable is shorted or OK. This simple 
modification will let you test good cables, 
and adds an extra level of cable fault find¬ 
ing to the Break Finder. 

A good cable can be tested if one end is 
removed from the Break Finder, and a 
small capacitor fitted in its place. This is a 
bit inconvenient, but a momentary DPDT 
pushbutton can disconnect the sockets on 
one side, and substitute a InF trimmer 

instead. If a balance can be achieved with 
the button pressed (and a cable attached to 
the other side), then the cable is OK; if not, 
then the cable is shorted. To balance the 
extra switch capacitance, a trimmer can be 
fitted to the other side and be adjusted for 
50% balance without any cables inserted. 

With this modification, the sequence for 
testing a cable would be as follows: 

Try to balance for a break in the usual 
manner. If this is not achieved, then bal¬ 
ance for the total cable by unplugging the 
cable from the switched side of the tester 

and pressing the button. 

If a balance still can’t be achieved, then 
the cable is most likely shorted and a low- 
ohms meter would determine the likely break 
point by comparison of both ends. 

Note: Cables in the sound industry have 
capacitances of around 90pF to shield and 
60pF between conductors per metre 
length, so a InF (lOOOpF) trimmer could 
easily balance cables between 1M and 
100M in length. 

Victor Erdstein 
Highett, Vic. $30 

Novel running light display 

Running lights or ‘chasers’ are nothing new, 
but this one is simple and versatile: The num¬ 
ber of LEDs in a group can be selected, as can 
the number of spaces between them as the 

pattern repeats. I used this circuit to create a 
pendulum for a mantle clock by using 16 
dual-colour LEDs arranged in an arc and with 
four shift registers. The pendulum (a group of 
three ‘on’ LEDs) swings in green colour from 
left to right and back again in red. 

The circuit shown consists of two dual shift 
registers (IC2 and IC3) and a quad NOR gate. 
IC1 a and b are wired as an RS flip-flop. It is set 
at switch on via the 0.1 uF capacitor at pin 1, 
forcing its output (pin 4) high. Simultaneously 
the registers are reset via the lOnF/lOk network 
at pins 6 and 14 on both registers. The remain¬ 
ing gates IClc and d form an oscillator with 
variable frequency via the 500k pot. 

On the rising edge of each clock pulse, the 
data at pin 7 is loaded and shifted from left to 
right (CW). The reset pin of IC 1 b connects 
to Q2 (the third output of IC2), so when this 
goes high it resets the flip-flop, pulling the 
data input low. The three LEDs now lit ‘shift 
around’ until the last output goes high (Q3 of 
IC3 high), which sets the flip-flop again and 
the cycle repeats. 

The pattern produced resembles a group of 
lights chasing around the circle continuous¬ 
ly. The circuit can be expanded by adding 
one or more shift registers in series, where 
one of the last outputs of the chain is con¬ 
nected back to the ‘set’ input of the FF. 

Programming is easy, for example: 
required string of 20 LEDs and group of five 
LEDs chasing, solution: three series-con¬ 
nected shift registers are needed, the reset 
line connects to the fifth output in the chain, 
the fourth output (the twentieth in the chain) 
of the third register connects back to the ‘set’ 
input of the flip-flop. 

Manfred Schmidt 

Edgewater, WA $30 


ELECTRONICS Australia, September 1998 

As an added incentive for readers to contribute interesting ideas to this column, the idea we 
judge most interesting each month now wins its contributor an exciting prize, in addition to 
the usual fee. The prize is a complete closed circuit TV system, comprising a 5” B&W video 
monitor, CCD video camera with stand, power supply and cabling. This system comes from 
our sponsor Allthings Sales & Services, and is valued at $369.00! 

Universal IR Controller 
for a PC 

This simple circuit allows you to record any IR 
remote control signal on your PC, and then play 
it back. This is particularly useful if you want to 
control appliances such as TVs, VCRs, CD 
players etc., from your computer. The device 
simply connects to the parallel port of your PC, 
and you can also use this circuit to analyze the 
waveform from any IR remote control. 

The circuit consists of two parts. The first part 
is the IR receiver, made up with an OP-505 IR 
photo transistor. This signal is buffered and 
squared up by the Schmitt trigger inverters 
(74HC14). The output of the second inverter 
goes directly to the Acknowledge line (pin 10) 
of the parallel port. The software polls this 
line in the recording mode and stores the 
incoming data sequence. 

The transmitter consists of a clock generator 
(555) set to run at 80kHz, connected to a 
74LS74 D-type flip-flop. The flip-flop divides 
the clock signal by two, giving a precise 50-50 
duty cycle on a 40kHz signal. This is then used 
as a carrier for the transmitter section of the 
circuit. In playback mode the software turns 
the DO line of the parallel port on and off at the 
same rate that it recorded the signal, which is 
used as a gate signal for the 40kHz carrier. The 
gate action is achieved by controlling the reset 
input of the D flip-flop. If the reset line is low, 

Low current bar-graph display 

then the Q output is also held low. 

This gated signal is then used to drive the IR 
LED via the driver section. The IR LED driver 
section consists of a 7405 hex open-collector 
buffer. All the outputs of the 7405 are tied 
together to give enough current to drive the IR 
LED. The two 1N4001 diodes are used to step 
down the voltage to around 3V for the IR 
LED. This may seem to be a bit of overkill, but 
it does mean that you can drive several IR 
LED’s simultaneously. The 555’s frequency 
can be adjusted for remote controls whose car¬ 
rier frequency varies from the standard 40kHz. 

This bar-graph display achieves low current con¬ 
sumption by switching the LEDs in series, as 
opposed to the conventional parallel arrangement. 

Resistors R3 to R8 set the threshold voltages 
in 2V increments, from 2 to 10 volts. These 
resistors can obviously be changed in value to 
suit the desired application. As the input value 
exceeds 2V, Ul’s output swings low, turning 
on the constant current source based around 
Ql. Because the outputs of U2 to U5 are still 
low at this point, only LED1 will light. 

As the input voltage increases from 4V to 
12V, U2 to U5 will switch on consecutively, 
allowing current to flow through LED2 to 
LED5 respectively. Due to the constant current 
source, only 10mA will flow through the LEDs 
whether only one is on, or all of them are on. 

If the input voltage is below the minimum 
threshold, U1 will switch to + 12V, turning 
off LED1. The total current consumption is 
around 13mA when the LEDs are on, other¬ 
wise it falls to almost zero. 

Wayne Robjent 

Tuart Hill, WA $30 

The record/playback software can be obtained 
free of charge from http://www.geocities. 
com/SiliconValley/Lakes/7156, and it allows 
you to record/playback and view just about any 
IR remote control signal. The real fun begins 
when you write your own software to control 
your house. For example, a program can be 
easily written that automatically programs the 
clock on your VCR, TV and anything else. 
George Katz 

Manly Vale, NSW $40 ♦> 


Colour $199 

Tiny 36 mm x 36 mm 


Automatic:- White balance, Electronic Shutter, Gain 
Control, Sack Light Compensation. 297 934 Element 
A" CCD. Options:- 4.3 mm Pinhole Lens, Ceiling or Wall 
DOME. Accessories.- 3.6 mm to 12 mm Board Lenses. 

Ph 08 934-9 94-1 3 Fax 08 934-4 5905 

ELECTRONICS Australia, September 1998 



Construction Project 

‘Front End 9 for 
PC Audio Recording 

Like to try using your PC for CD-quality digital audio recording? Or for making your 
own CD copies of treasured old analog recordings? Most modern PCs and their sound 
cards are capable of doing things like this, but the job will be a lot easier if you build 
and use this handy ‘recording front end’. It provides stereo preamps for a magnetic 
pickup and microphone, combined with basic mixing and tone control facilities. 

by Jim Rowe 

It’s a bit of a squeeze , but with care everything fits into one of the small sloping-front 
instrument cases. 

O nly a few years ago, the equipment 
needed for high quality digital audio 
recording seemed way out of reach for 
most of us. High quality professional analog 
to digital converters had equally ‘profession¬ 
al’ price tags, and only dedicated profession¬ 
als could justify the cost of hard disk drives 
with the many hundreds of megabytes of 
storage needed — because with CD-quality 
stereo, you need over 10MB per minute. 

As for recording your own CDs, that 
seemed even more in the realm of fantasy... 

Happily, though, that’s all changed. Most 
modem PCs are fitted with sound cards 
whose A/D converters are capable of sur¬ 
prisingly good quality, and with hard disks 
of multi-gigabyte capacity. Even with the 
steadily expanding size of modem software 
(‘bloatware’), there’s still likely to be 
enough space to store the tracks for at least 
one CD’s worth of audio... 

When it comes to CD recording, you can 
also get CD-R ‘burner’ drives which are capa¬ 
ble of recording very acceptable (and fully 
compatible) DIY audio CDs, plus a variety of 
easy-to-use software to help you perform 
audio recording to hard disk, edit your digital 
audio files and then write them to a CD. So 
now, almost anyone with a reasonably mod¬ 
em PC can use it as the basis for a high qual¬ 
ity digital audio recording system — and for a 
lower outlay than you probably expect. 

One very attractive use for such a system 
is for making personal CD copies of old and 
treasured analog recordings — from old 
shellac ‘home recording’ discs, or old 
78/45/33.3rpm commercial pressings, or 
even old reel-to-reel magnetic tapes. As part 
of the copying process you can often take the 
opportunity to ‘clean up’ the old recordings, 
by removing irritating imperfections such as 
surface noise and crackle. There are now 
some excellent programs available to do this, 
like DART Pro 32 and Diamond Cut. 

If you’ve tried doing any of this copying, 
though, you’ve probably found that there’s 
more to it than simply hooking up your old 
analog turntable or tape recorder to your 
PC’s sound card. Things are never that easy, 
are they? 

For example most hifi turntables were fit¬ 
ted with a magnetic cartridge, which needs 
to be fed through a preamp with the correct 
RIAA equalisation in order to produce ‘flat’ 
signal levels suitable for feeding a sound 
card. And even though the signals from your 
tape recorder or deck might be adequate in 
level, you might want to do a spot of pre¬ 
equalisation — perhaps to boost the bass a 
little, or reduce the level of tape hiss, or cor¬ 
rect other deficiencies in the original record¬ 
ing. (It’s generally not a good idea to rely 
wholly on the software DSP facilities to 

bring the signals ‘up to scratch’...) 

You might also want to be able to hook up 
a microphone, to add some narration or a 
spoken introduction to the recordings you’re 
transcribing. Most sound cards do have a 
mic input jack, but this is usually not easy to 
access, and it’s often simply disabled when 
the line inputs are used. Generally it’s much 
more convenient to have an external mic pre¬ 
amp and mixing setup. (The performance 
can also be significantly better, because the 
response of the mic preamp in many sound 
cards is quite poor.) 

In short, there’s really a need for a flexible 
‘recording front end’ unit, to interface between 
the PC’s sound card and these audio signal 
sources, and provide gain and equalisation. 
Needless to say that’s the very purpose of the 
handy little unit described in this article. 


ELECTRONICS Australia, September 1998 

ELECTRONICS Australia, September 1998 


o iuf 12V plug pack or battery supply. 

Construction Project 

Front End for PC Audio Recording 

Here’s the overlay diagram for the PC board. There are only three wire links — one 
either side of U4, at upper right, and the third just above U5 and below C42. 

What it does 

Basically the unit consists of four circuit sec¬ 
tions: a stereo magnetic pickup preamp, with 
the appropriate gain and RIAA equalisation 
for ‘conditioning’ the signals from a magnet¬ 
ic pickup; a stereo mic preamp, with suffi¬ 
cient gain to operate with most common 
dynamic or electret microphones; a simple 
two-input stereo mixer, to allow control of the 
signals from the mic preamp and either the 
magnetic pickup preamp, or a Tape/Line level 
stereo input; and finally an active tone control 
circuit with bass and treble controls, each 
capable of around 12dB of either boost or cut. 

It all fits in a compact sloping-front utility 
box, and operates from a low cost nominal 
12V DC plug pack supply (or a 12V battery 
supply, if you prefer). 

With the unit, your PC and its sound card 
are provided with all of the basic facilities 
for convenient digital audio recording. 

By the way, the facilities it provides real¬ 
ly aren’t restricted to use with a PC sound 
card. You could also use it as a very basic 
‘recording console’ for commercial audio 
CD recorders and DAT recorders... 

How it works 

Each of the four functional circuit sections is 
based on an LM833 low noise dual op-amp, 
as you can see. The mic preamps use U1, the 
magnetic pickup preamps 
U2, the mixer stages U3 
and the tone control stages 
U4. We’ll now look at 
these briefly in turn. 

The mic preamp stages 
(Ula/b) are quite conven¬ 
tional, with negative feed¬ 
back used to determine 
the voltage gain. Switch 
SW2a/b allows the gain of 
each stage to be set to 
either ‘High’ or ‘Low’, 
corresponding to a total 
gain of around 1050 or 
300 respectively (60dB or 
50dB), to suit either low 
output or higher output 
microphones. The fre¬ 
quency response of the 
mic preamps is essentially flat, within 2dB 
from 35Hz to 18kHz. 

The magnetic pickup preamps (U2a/b) are 
also quite standard, using a well-proven con¬ 
figuration and circuit values as used in Rob 
Evans’ recent Playmaster Pro Series Control 
Unit No.4. The feedback circuitry (R12-15, 
Cl2-14 etc.) gives a very close approxima¬ 
tion of the correct RIAA equalisation char¬ 
acteristic, to ensure a clean and balanced 
output from the majority of magnetic car¬ 
tridges (moving magnet type). The preamp 
gain is around 35dB at 1kHz. 

As you can see the output of the magnetic 
pickup preamps is taken to switch SWla/b, 
which allows you to select either the magnet¬ 
ic pickup signals or those at the Tape/Line 
level inputs, as your inputs for the ‘PU/Tape’ 
channel of the mixer — controlled by ganged 
volume pots RVla/b. The outputs from the 
mic preamps are taken directly to the ‘Mic’ 
channel volume pots RV2a/b. 

The mixing stages (U3a/b) are again very 
conventional, with resistors R25-27 and 
R28-30 used to achieve low interaction ‘vir¬ 

tual earth’ mixing of the two input channels. 
With the resistor values shown the maxi¬ 
mum mixer gain is two (6dB), and this 
becomes the ‘flat’ gain of the complete cir¬ 
cuit for signals fed into the Tape/Line inputs. 

The tone control stages (U4a/b) are also 
quite standard, using the time-honoured 
Baxandall feedback circuit. This provides 
bass and treble controls, each with the abili¬ 
ty to achieve up to about 12dB of boost or 
cut (at 50Hz and 15kHz respectively), and 
with very little interaction. In the ‘flat’ posi¬ 
tions of the controls the overall response is 

within ldB from below 30Hz to around 
25kHz — significantly better than most 
sound cards themselves. 

The mixing and tone control circuitry has 
the ability to provide over 6Vp-p output before 
clipping, into the line input circuitry of a typi¬ 
cal PC sound card (roughly 40 - 50k£2in par¬ 
allel with about InF). This means that at the 
2Vp-p maximum input level needed by the 
Line inputs of most sound cards, the distortion 
is quite low — typically less than 0.05%. 

The op-amps in all four signal processing 
sections of the unit operate 
from regulated +/-5.5V sup¬ 
ply rails. These are derived 
from the nominal 12V DC 
input by a simple on-board 
power supply circuit. 
Regulator U5 provides the 
+5.5V rail directly, while 
the negative rail is generat¬ 
ed by a simple polarity- 
inverting circuit which uses 
555 timer U6 as a self-oscil¬ 
lating power chopper, dri¬ 
ving C40/41 and D2/3 as a 
charge-pump rectifier dri¬ 
ving negative regulator U7. 
With a nominal 12V DC 
input the negative voltage 
generated across C41 is 
around 9.5V under load, 
giving plenty of ‘headroom’ for U7. 

Note that in this project the inverting chop¬ 
per U6 is intentionally operated at around 
70kHz, to minimise the possibility of interfer¬ 
ence with either the audio signals themselves 
or the sampling clock of the PC sound card. 

As you can see both U5 and U7 have 
1N914 (or similar) diodes in series with their 
common lead, to increase their outputs by 
about 0.5V. This has been done to allow for 
the voltage drops in decoupling chokes L3 
and L4, ensuring that preamp chips U1 and 
U2 still receive more than the minimum 

An audio preamp/mixer/tone control unit to facilitate digital audio recording with 
a PC and sound card. 

Magnetic Pickup Preamps: Low noise, provide full RIAA equalisation for use 
with moving-magnet cartridges. Provide approximately 35dB gain at 1kHz (total 
effective gain 41 dB). Input impedance 50k. 

Microphone Preamps: Low noise, provide selectable total effective gain of 
either 1050 (60dB) or 300 (50dB) to suit mic output. Response flat within 2dB 
from 35Hz to 18kHz. Input impedance 100k. 

Mixer: Basic two-channel active stereo mixer, able to control levels from Mic 
and Pickup-Tape/Line inputs independently. Tape/Line input sensitivity 350mV 
RMS for 2Vp-p output at 1kHz; input impedance 50k. 

Tone Controls: Active Baxandall type, with independent bass and treble 
controls providing up to 12dB boost or cut at 50Hz and 15kHz. The ‘centred 
controls’ response of mixer and tone control stages is flat within IdB between 
20Hz and 20kHz, with in-band noise around -70dB below 2Vp-p output. 

Power Source: 11 - 15V DC, from external plug pack supply or battery. 

Current drain approximately 95mA, power consumption 1.2 watts. 


ELECTRONICS Australia, September 1998 

m out 

I R 

Use the inside view above as a guide when 
you're wiring up your own unit. Note, 
however, that the wiring to the tone controls 
and mic volume pots should be dressed so 
that it is kept as far away from the power 
supply chopper circuitry (i.e., U6, C40-41 etc) 
as possible, when the case is closed. This 
minimises pickup of the 70kHz switching 
signal. Note also that this prototype uses an 
earlier version of the PCB, which had no 
provision for on-board mounting of output 
series resistors R51-52 — that’s why they're 
visible ‘hanging off the output terminal pins. 
At right is a rear view of the assembled unit. 


L R l R 

•) Q m (# 0 

mL _rr—.. . . 

ELECTRONICS Australia, September 1998 


‘Front End’ for PC Audio Recording 

Construction Project 

At left is the PCB etching 
pattern for the project , 
while at right on the facing 
page are the patterns for 
the front and rear panels. 
All are shown actual size 
so they can be used for 
making your own if you 
wish. Photocopies can 
also be used as templates 
for drilling the holes in 
your case. 

allowable voltage (+/-5V). 

By the way, the schematic shows the pro¬ 
ject’s allowable DC input voltage range as 11- 
15V. At the top end this allows a comfortable 
margin for the 555 chip (U6), which has a 
maximum voltage rating of 18V. If you do use 
a plug-pack supply with a nominal DC output 
of higher than 12V, make sure it doesn’t rise 
above 18V under light loading conditions. 


The unit is housed in a small sloping-front 
utility case, with most of the components 
mounted on a PC board measuring 139 x 
70mm, and coded 98rfe9. The PCB mounts 
horizontally in the bottom of the case, with 
the controls mounted on the sloping front 
panel. The input and output connectors are 
mounted along the rear of the case. 

The case used for the prototype measures 

190 x 120 x 65/36mm, but other similar cases 
may be compatible — the main thing to watch 
is the minimum internal height, to ensure clear¬ 
ance between the components on the PCB and 
those on the front panel. Things are fairly tight, 
especially just below the two mixer pots. 

Because the case is predominantly plastic, 
and provides very little shielding, a small 
‘shield plate’ cut from unetched PCB lami¬ 
nate is mounted under the main PCB, with its 
copper layer connected to signal earth. The 
metal front panel and the controls mounted 
on it are also earthed, for the same reason. 

The overlay diagram and internal photos 
should give you a good idea of where every¬ 
thing goes, and its orientation. I suggest that 
you begin construction by fitting all of the 
smaller components to the PCB, using the 
overlay and schematic as a guide. 

It’s easiest if you begin by fitting the PCB 

terminal pins first; there are 42 of these, 
used for all of the off-board connections. 
Then fit the three wire links and all of the 
resistors, as they’re all mounted horizontal¬ 
ly and have a low profile. You can follow 
these with the three power diodes D1 - 3 and 
signal diodes D4-5, making sure that they’re 
all orientated correctly. 

If you’re going to use DIL sockets for the 
five ICs, these could now be fitted. (It’s up to 
you whether sockets are used, as the argu¬ 
ments for and against are closely balanced. 
Sockets will allow convenient replacement of 
chips in the future, but are also in themselves 
a significant source of unreliability. They 
were only used in the prototype unit pictured 
to allow testing of different chips during 
development of the project. If I were building 
up another unit myself, I’d forget the sockets 
and fit the ICs directly to the board...) 




All 0.25W, 1% 

metal film unless specified: 





0.47uF MKT 


180 ohms 


47uF 3VW TAG tantalum 






O.luF monolithic 




lOOpF ceramic 


150 ohms 


2.2uF 16VW TAG tantalum 




220uF 10VW RB electrolytic 


82 ohms 


220pF ceramic 




18nF MKT 


39 ohms 


68nF MKT 










4.7nF MKT 




lOOOuF 16VW RB electrolytic 




3.3nF MKT 




220uF 16VW RB electrolytic 


470 ohms 


lOOuF 10VW RB electrolytic 


Dual 50k log pot 



Dual 100k linear pot, 



centre indent 


7805 +5V regulator 


Dual 25k linear pot, 


LM555 timer 

centre indent 

U7 7905 -5V regulator 

Dl,2,3 1N4001 power diode 

D4,5 1N914 (or 1N4148) diode 


L1.L2 8T 0.25mm ECU on 

F29 ferrite bead 

L3,L4 ImH RF choke 

SW1,2 Miniature toggle switch, DPDT 

LED1 3mm red LED 

Sloping-front case, 190 x 120 x 65/36mm or 
similar; PCB, 139 x 70mm, code 98rfe9; piece 
of unetched PCB laminate, 139 x 70mm, for 
shield plate; 42 PCB terminal pins; five 8-pin DIL 
sockets (optional); front panel dress plate, 175 x 
100mm; rear panel dress plate, 175 x 25mm; 
six RCA sockets, panel mount; 3.5mm stereo 
jack socket, panel mount; 2.1mm or 2.5mm 
concentric power input socket, panel mount; one 
screw terminal, black; shielded audio cable, 
rainbow ribbon cable for off-board connections; 
four 12mm x 3mm dia machine screws, 
countersink head, with eight matching nuts and 
star lockwashers; solder, etc. 


ELECTRONICS Australia, September 1998 

Next you can fit the smaller ceramic and 
MKT capacitors, followed by the larger 
MKTs, TAG tantalums and aluminium elec- 
trolytics. (Take care with the orientation of 
the latter parts, as they’re polarised.) Then 
you can fit the two decoupling chokes L3 
and L4, and wind the two small RF suppres¬ 
sor inductors LI and L2 — each of which is 
made from eight turns of 0.25mm enamelled 
copper wire on a single-hole ‘bead’ of F29 
high-frequency ferrite. 

With the passive parts all fitted to the 
board, I suggest that you next fit only the 
three power supply ICs: inverting chopper 
U6 and regulators U5 and U7. The latter 
both mount horizontally, with a 9mm x 3mm 
diameter machine screw and nut to attach 
them securely to the board and provide 
minor additional heatsinking. 

With these fitted, and before you fit the 
four op-amp chips, you can connect up the 
board to the plug pack supply or another 
convenient source of 12V DC, and make 
sure the power supply section is working as 
it should. This will help avoid possible dam¬ 
age due to wiring errors. 

With the 12V source connected, a DMM 
should be able to measure +5.5V at the out¬ 

put pin of U5 (the pin nearest C27), and - 
5.5V at the output pin of U7 (the pin nearest 
C43). Similarly you should find about 
+ 11.5V at pin 8 of U6, and around -9.5V at 
the anode of D3 (the end furthest from R49, 
towards the end of the PCB). 

If these voltages all check out correctly, 
you can switch off the supply and confident¬ 
ly proceed with the assembly by fitting the 
four op-amp ICs (Ul-4). Your completed 
board assembly can then be placed aside 
while you prepare the case. 

A photocopy of the front panel artwork can 
be used as a template for drilling and reaming 
the holes in the panel for the pots, switches 
and LED. I suggest you use the actual con¬ 
trols as a guide to the final holes sizes, as 
bush sizes can vary significantly. You might 
also want to drill ‘blind’ holes from the rear 
of the panel, to accept the locating spigots for 
the pots and switches; this prevents them 
from rotating later, without the need for 
excessive tightening of the mounting nuts. 

If you’re using a dress panel based on our 
front panel artwork, this can be applied care¬ 
fully after the panel is prepared, and the 
holes cut out with a hobby knife using those 
in the main panel as a guide. 

With the panel now prepared, I suggest 
that you fit the LED into its close-fitting 
3mm hole, and cement it in place with a dob 
of epoxy glue or similar at the rear. The 
panel can then be placed aside for a while, to 
allow the glue to set. 

The holes for the rear connectors can be 
drilled and reamed next, using the connector 
ID label artwork as a guide. Most of the con¬ 
nectors are single-hole RCA sockets, which 
need a hole 6mm in diameter. This is also the 
hole size needed for the 3.5mm mic jack. 
The size of the holes for the power connec¬ 
tor and turntable earthing terminal will 
depend on these components themselves. 

The only remaining holes are those for 
mounting the PCB assembly in the bottom 
of the case. These are 3mm in diameter, and 
can be marked out using a photocopy of the 
PCB artwork as a template. If you’re using 
countersink-head screws as I did, you’ll 
need to countersink the holes on the outside 
of the case to suit. 

If your 139 x 70mm rectangle of unetched 
copper (for the shield plate) is not already 
drilled, you can use the PCB artwork copy as 

(Continue J on page 73) 

ELECTRONICS Australia, September 1998 49 

15 — Designer door alert 

This twin-tone door alert is 
not intended to be a 
raucous alarm to wake the 
whole family. Instead, it 
produces a well-bred signal 
that someone is waiting 
patiently (we hope!) for you 
to answer the door. It can, 
of course , be used 
anywhere you want a more 
friendly tone , such as a 
shop doorway alarm where 
you don’t want to scare off 
the customer... 

T his project is called a ‘Designer’ alert 
because you can tailor the sound to suit 
your own preferences, simply by making 
a few modifications to the circuit connec¬ 
tions. (I’ll go into more details on this later.) 

Pressing a switch activates the alert and, 
since this is a fairly simple and inexpensive 
circuit to build, the price of a real front 
door push-button is included in the ten dol¬ 
lars — but any kind of switch will operate 
it. For example, it could be used in a shop 
to warn you that a customer is waiting, with 
a micro-switch attached to the shop door. 
Or you could fix a suitable switch to the 
front gate to inform you that visitors are 
imminent. Athough its basic sound is rea¬ 
sonably genteel (but insistent enough to be 

+6V o - o o -- 


easily heard), you can, if you want, pro¬ 
gram it so give a much more demanding 
‘Hurry-up-l’m waiting’ clamour. 

How it works 

The sounds are generated by an oscillator 
included in IC1 (Fig. 1), which also contains 
a 14-stage binary divider. The frequency of 
the sound is determined by the values of Cl 
and R2, where f= 1/(2.2RC). 

With the values given in Fig. 1 the clock 
frequency is almost exactly 20kHz. This 
goes through four stages of binary division 
before we see it again at pin 7. Four binary 
stages are equal to division by 16, so the 
signal at pin 7 has a frequency of 1.25kHz. 
This is comfortably within the audio range 

and makes a suitable basic frequency for the 
rest of the circuit’s operation. 

To obtain a two-tone signal we require a 
second frequency, which we pick up from 
further along the divider chain. In the cir¬ 
cuit we are showing here we are using the 
output from stage six, which is one quarter 
the frequency of stage four — in other 
words just over 300Hz. 

Further still along the chain, the frequen¬ 
cies drop below the audio range. For exam¬ 
ple at stage 13 the frequency is 20kHz/2 13 = 
2.44Hz. This is inaudible (except as distinct 
‘clicks’), but is useful enough for control¬ 
ling the two-tone effect. We’ll refer to it as 
the control signal. 

The two audio signals from pins 7 and 4 

Table 1: Frequencies available from IC1 
(relative to the basic frequency at pin 7) 


Relative freq. 



) Suitable 



) for 



) audio 



) signals 







) Suitable 



) for 



) control 



) signals 

Fig.1: The heart of the circuit is IC1, which combines a ‘clock ' oscillator with a 14-stage 
binary counter. We use selected outputs from IC1 to both make the audio tones and 
control them, via IC2. 



ELECTRONICS Australia, September 1998 

by Owen Bishop 

Fig.2: Here’s the 
wiring diagram 
for the door 
alert, as built on 
a piece of 

23456789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 

are taken to a pair of NOR gates in IC2 
(gates a and c). Each of these also receives 
a version of the control signal. Gate a 
receives it directly, while gate c receives it 
after it has been inverted by gate d. Gate d 
has its two inputs wired together so it oper¬ 
ates as an inverter (or NOT) gate. 

When the control signal is low, gate a 
passes the 1.25kHz signal and (since the 
inverted control signal is high) the output of 
gate c is held low. On the other hand when 
the control signal is high, the 300Hz signal 
passes gate c and the output of a is low. The 
outputs of a and c are fed to gate b which 
acts as a mixer. 

In this way transistor Q1 receives the two 
audio signals alternately. The transistor 
switches current through the loudspeaker 
and we hear a two-tone sound. 

Design options 

For anyone with time to spare, there is quite 
a lot of scope for playing around with the 
values and connections in this circuit, and a 
varied range of effects is possible. Here are 
some pointers to get you started: 

• The basic tone is set by the frequency of 
the oscillator. Set this by choosing suit¬ 
able values for R2 and Cl, remembering 
that the frequency is divided by 16. 
Having done this, make the value of R1 
around 10 times R2. If you want a really 
high tone, you can take the signal direct 
from pin 9. Just remember that you 
might not hear it if the oscillator is 
working above 15kHz and your ears are 
not as young as they were! If so, try 
increasing Cl a bit. 

• The frequency of the alternate tone is 
derived by tapping the divider chain at 
different points. We have tapped stage six 
to get a 4-to-1 frequency ratio. Other tap¬ 
pings produce quite different sounds and 
Table 1 shows what is available. 

• The rate of tone change is decided by 
where the control tap is placed. Generally 
stages 10 to 14 are the most suitable, but 
interesting warbling effects are produced 
by using one of the earlier stages. 

• There is no volume control in this circuit. 
Volume is plentiful with R3 as shown, 
but you could increase R3 to produce a 
softer tone. 


The circuit is intended to operate on 6V, 
either from a 6V mains plugpack (non-regu- 
lated) or a battery pack of four AA cells. 
Since it takes current only when the button is 
pressed, the batteries should last you a long 
time. The project is best housed in a small 
plastic box, with an aperture cut for the 
speaker. We used a 40mm Mylar miniature 
speaker, which is easily glued to the panel by 
its rim. Firm mounting is essential if you 
want maximum sound volume. 

If you want to experiment with the con¬ 
nections, it is best to wire up the circuit on 
a breadboard, and start tinkering! There’s 
lots of room on the stripboard to make 
changes to the circuit if you change your 
mind later on. 

Assemble the circuit on stripboard (Fig.2) 
noting that the strips are cut in some places 
beneath the board, but NOT at C10 and F10. 
Solder blobs can be used to join adjacent 
strips at certain places, including pins 12 
and 13 of IC2. You may decide to alter 
some of the connections between the ICs 
(the orange wires in the photo) either now 
or later. ❖ 

Parts List 


Carbon or metal film 5 %, 0.25 W 

R1 47k 

R2 4.7k 

R3 2.2k 


Cl 4.7nF MKT or greencap 


IC1 4060 14-stage counter/divider 

with oscillator 

IC2 4001 quad 2-input NOR gate 

Q1 BC338 NPN transistor 


SW1 N/0 pushbutton switch 

LSI Miniature loudspeaker, 8Q, 1/4W; 

Matrix board 17 x 39mm (10 strips x 26 
holes); 3 x 1mm terminal pins; 14-pin 1C 
socket; 16-pin 1C socket; wire for linking 
push-button to circuit. 


You’ve seen the BASIC Tiger and Tiny Tiger 
advertised in the US magazines: they are 
now available in Australia from JED. 

Tigers are modules running true complied (not 
tokenised), Multitasking BASIC at 20 Mhz, but only 
draw 45mA. They have memory, 4 x 10-bit analog 
inputs, digital 1/0, two serial ports, RTC, and are 
superb small controllers for scientific and 
industrial applications. A Tiger with 128kB 
FLASH, 128kB CMOS RAM and RT clock costs 
only $162.A development system (W95), with a 
proto board, is only $275. JED has a local 
board/controller with LCD/Kbd and industrial 1/0. 

See our www site or call for data sheets. 

Three PC/104 single board computers 
based on 
X86, one 
5 UARTs, 

LPT & 

! JBUS. 

The PC540 (at $350) uses an 80C188EB, with 40 
1/0,2 UARTs & timers uses $179 Pacific C. 

The PC541 is a V51 PC/XT DOS computer with 20 
1/0, PC UARTs, LPT, FDC IDE disk. The new PC543 
uses an AMD ELAN (386) cpu at 33 Mhz with 4 MB 
DRAM, 16 MB FLASH, five RS232 (2 opt. RS485), 
LPT and JBUS. (All have JBUS, JED’s 26-pin ribbon 
cable bus for industrial 1/0. All boards are 
3.6” by 3.8”on the PC/104 bus, and range from 
$350 to $500.) 

$300 PC-PROM Programmer 
Also: $145 Eraser with timer. 

This programmer plugs into a PC printer port and 
reads, writes and edits any 28 - pin or 32 pin PROM 
without needing special plug-in cards. 

JED Microprocessors Pty Ltd 
173 Boronia Road, Boronia, 3155 
Ph 03 9762 3588 
Fax 03 9762 5499 

(prices do not include freight or sales tax.] 

ELECTRONICS Australia, September 1998 







A quality tool that 


Standard Typem^ 

Normally $4.75ea 

$3.75ea or 
10 for $30 

Cat. SB-2440 


Solder Tags 

Normally $4.95ea 

$3.95ea or 
10 for $32 

Cat. SB-2441 


Digital quality sound with fully 
adjustable headband and soft leather 
padded ear cups. Gold plated 3.5mm 
stereo plug with adaptor for 6.5mm. 
Frequency 18Hz to 22kHz. 

Only $19.95 Cat. AA-2006 







will find wooden 
studs, metal, 
nails, screws and 
voltage. When anything 
is detected, a LED will 
light up next to the 
corresponding symbol - 
and a buzzer will sound. 

Includes a 2 way switch, 
one position for studs, 
the other for metal and 
voltage. Also has a low 
battery warning. Uses a 
9V battery not supplied. 

Size 175x38x23mm. Cat. QP-2280 

Only $29.95 


Brand new batch. 

Contains a minimum of 
100 pieces. Packs may 
include transistors, ICs, 
diodes, and there may 
even be a bonus in 
there!! We do know that 
at $10, it represents an absolute 
bargain! Note Picture is a 
representation only. C+j|| Ollly 
Cat. ZP-8990 $ 1 () 


NOKIA 1610 

Ni-Mh 1200mAh. 

Standby 100 hours. 

Talktime 360 mins. 


Hides behind a 
pinhole! Includes 
BNC & power 
socket. For 
specs, see 
QC-3470 on 
200, in 
our 98 Cat. 

Cat. QC-3471 

NOKIA 6110 

Ni-Mh 950mAh. 
Standby 80 hours. 
Talktime 280 mins. 


Cat. SB-2552 


Cat. SB-2554 


Ni-Mh 600mAh. 
Standby 30 hours. 
Talktime 90 mins. 


Cat. SB-2577 


NOKIA 3110/3810 

Ni-Mh 1200mAh. Standby 120 hours. 
Talktime 280 mins. Cat. SB-2553 


ERICSSON 628/688 

Ni-Mh 1200mAh. Standby 100 hours. 
Talktime 360 mins. Cat. SB-2576 



Made by YOGA, the company that 
makes all our microphones! These 
feature *High compliance 50mm 
diaphragm »High performance cobalt 
magnet ‘Single side cable entry *ln line 
volume control ‘Gold plated 3.5mm 
stereo plug with adaptor for 6.5mm 
•Frequency 18Hz to 22kHz. 

Only $44.95 Cat. AA-2008 


12 V, 15 V, 18V 
DC 800MA 

Has switchable voltage and polarity. Output lead is 4 
way moulded star plug which has 2.5mm & 3.5mm 
plugs & 2.1 mm and 2.5mm DC plugs and a 1.3mm DC plug. 

Cat. MP-3034 

Ni-Mh 1200mAh. Standby 60 hours. 
Talktime 180 mins. Cat. SB-2582 

12V 150W /% 



D9 Female to RJ45 Female. 

Cat. PA-0906 $5.95 


Cat. NS-3020 
WAS $2.95 { 


!TI1#E # 




Cat. XC-4710 


Now in 4 
colours. Ideal 
for house, 
shop, display 
and garden lighting. 
Large size - 51 mm dia. 
38° wide angle. 

50 watt. 

RED SL-2741 

GREEN SL-2742 
BLUE SL-2743 


Will deliver 150W 
RMS into 412 and 

100W RMS into 
812. Make your 
own active 
subwoofer. See 
98 Cat. page 57 
for details. 

Cat. AA-0500 


Pkt. 25 Pkt. lO 
was was 
$15.95 $5.95 

$11.95 $4.95 

Save $2 Save $1 

XC-4740 XC-4739 

COLOURE disks 

Pkt 25 
Was $14.95 

NOW $12.95 

Save $2 

Cat. XC-4742 

91# AC 1 AMP 

Grab some of these while you can. 

Surplus stock purchase of 240V AC 
adaptor plugpacks to 9V AC at 1 
AMP. Terminated to a 2.5mm DC plug. Cat. MP-3024 



Buy 10 $8ea. Buy 50 $7ea. 

(3CSX7 [&D®g)®t? GQQ!X30DGflG£7 GODDGGQGG ©CM? 

\5!7DO®D©S(Ifi© ©©[oXHCPGnuQQDQGo 


Holds 3.5” disks, minidata 
cartridges or MD disc 
cartridges. See Cat PI 94 
for details. Cat. XC-4675 

was $19.95 
Save $4.00 


Includes 2 lights and really nifty on/off 
switch with 

wiring loom 

hardware. Size 
x 85(D) mm. 

Cat. ST-3070 

The ultimate in burglar alarm PIRS. Requires 
both the PIR & Microwave to be triggered at the 
same time, substantially reducing false alarms. 

was $79.95 Save $10 Buv a for <220 
September $69.95 

Cat. LA-5012 




For full specs see cat PI 21. 


September $15.95 





Cat. QM-6320 


Includes a clock. 
Count up and down. 
Includes a host of 

Cat. XC-0284 


MAGNETIZER / cat lt -airs Was $34.95 


I . i — Save $5 


Cat. LT-3181 was $45 

sept. $39.00 

Cat. LT-3182 was $79.95 

. $6 

screwdrivers makes 
life easier. 

Cat. TD-2042 


This guard prevents 
the car battery from 
running down 
by switching 
off automatically 
when the battery 
falls below 
11.2 volts. 

Supplied with 

cigarette lighter plug and socket on lead. 

Simply connect the device being used in line. 
Maximum current is 10A. 

Cat. AA-3092 Only $29. 


500,000 CANDLE POWER. 
Cat. ST-3023 


■' ' // \ ' 

Cat. TD-2082 




sept. $20 


Cut any shape in aluminium, 
plastic, copper and 
unhardened metals to 18 
gauge.Cat. TH-1768 

Normally $21.95 

Ideal for kitchen. Accuracy 
+/- 0.5%. Resolution 1 
gram/1 ounce. 

Cat. QM-7245 $55 

Cat. HP-0638 

Leave both hands 
free! Flip up 
when not 
in use. 4 

multiples. See 
98 Cat. page 185 
for details. 

Cat. QM-3510 




ofr fhon 


Plug it Into computer games, stereos etc, then 1 
put the back pack on and feel all the low frequency 
sounds. See 98 Cat. page 213 for full details. 

Cat. XC-1000 ■■■ ft 


This pack contains all the leads required to attach the Aura 
Interactor to your games console and stereo system. Includes RCA 
piggyback lead, 3.5mm phone to 2 x RCA adaptor lead, RCA joiners 
and stereo Hi Fi RCA cable. Total value $17.40 
Cat. XC-1001 $11-95 

Massive Distress Stock Purchase 

Ideal for monitoring your front door, or the baby, etc. Includes a 
10” black and white monitor, CCD camera in a metal case with 
mounting bracket and 20mts. of cable. The monitor will accept up 
to 4 CCD cameras, and these can be manually or automatically 
switched between them. Any of our CCD cameras can be used 
with this monitor. There is a talk function between the camera and 
the monitor which has outputs to a video recorder. The monitor 
runs off mains power, and the camera is powered by the monitor. 

Extra cabling & the 6 pin mini plug are available. 

Cat. QC-3490 

Only $499 





See 98 Catalogue pages 42/43 
for full details. 


5” woofer and Vifa dome tweeter. 




Buy both togethei 

JC30 6" 2 WAY 

6” woofer and Vifa dome tweeter. 



Buy both together $409 

JV60 6" 3 WAY KIT 

Includes 2 x 6” Vifa woofers and Vifa dome 


Buy Together for $849Pr 



No one seems terribly interested in the fact that mobile 
phones may fry your brains! Now you don’t have any excuses! 



Cat. ST-3102 


Motorola 8200, 8400 
Motorola Flare 
Motorola 8500, 8700 
Nokia 2110 
okia 1610 
okia 8110 
Nokia 5110 
Ericsson 518/388 
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Construction Project 

Baby Alarm 

Here’s an interesting and low cost project based on the popular BASIC Stamp 
microcontroller module. It’s a flexible baby minder, which is easy to build and program 
(from your PC), but also offers plenty of opportunities for adding extra ‘frills’. 

by Owen Bishop 

The ‘works’, with the BASIC Stamp visible at lower centre. 

T his is a BASIC Stamp (or Counterfeit) 
micro-based project, which can look after 
baby more ‘intelligently’ than the typical 
alarm system. Although it can be pro¬ 
grammed in Immediate mode to sound the 
alarm every time baby makes a tiny snuffle, 
the project works on the assumption that we 
are not interested in the occasional sneeze, 
cough or whimper that baby makes. It is only 
when there are several such sounds within a 
given period of time that we need to be 
informed about it. 

In its Normal mode the alarm registers 
each disturbance, but it sounds the alarm only 
when it has recorded a significant number of 
disturbances within a few minutes of each 
other. It is programmed to have a relatively 
short memory, so that sounds made a few 
minutes ago are automatically ‘forgotten’. 
The parameters of the Normal mode can be 
set both for the recording time interval and 
the critical number of detected sounds. 

The third mode, called the OK mode, is 
one that is a novelty for baby alarms. This 
gives us a reassuring beep or two every 10 
minutes or so if it has detected no sounds in 
that period. Nice to know that baby is sleep¬ 
ing quietly! The OK mode also includes the 
Normal mode function and you can set dif¬ 
ferent parameters for sounding the alarm. 

The alarm sounder, or audible warning 
device (AWD) recommended for this system is 
a low-level piezoelectric beeper. A device such 
as this is perfectly adequate for normal domes¬ 
tic use. You could use a 120dB siren instead 
and rouse the whole neighbourhood every time 
baby hiccups, but do you really need to? An 
LED is mounted beside the bleeper so we have 
both audible and visible warnings. 

Certain types of alarm system relay the 
actual sounds from the nursery, but we find 
this irritating — especially to guests. The 
low-level beeper is much more discreet and 

provides the warning just as effectively. 
When the alarm is triggered, the AWD gives 
five short beeps and then remains silent for 
20 seconds. This gives you time to go to the 
nursery, reset the system, and attend to baby. 
The beeping is repeated every 20 seconds 
until you do this, for there is no way of 
switching off the alarm in the living room. 
Discreet, but persuasive! 

How it works 

This design leaves scope for several modifi¬ 
cations according to your preferences, so we 
have built it on stripboard. Fig. 1 shows that 
the circuit is, as usual, centred around the 
Stamp module, plugged into SKT1. The 
other socket, SKT2 is for the programming 

lead, connected to the PC during the initial 
stages of testing and setting up the circuit. 

The system runs on 6V DC and needs only 
13.5mA when quiescent and about 60mA 
when beeping. This means that it should run 
for over 100 hours from a set of four type 
AA alkaline cells in a battery-holder. Or you 
can use a 6V DC (must be DC, but can be 
unregulated) plug-pack. 

The circuit has an LED (LED1) acting as 
a pilot lamp. This is on the main board and, 
since this is in the darkened nursery, we have 
used a 330Q series resistor to limit the cur¬ 
rent to about 10mA. This gives quite enough 
light to be seen in a semi-darkened room. 
SW1 is the reset button; pressing this resets 
the Stamp to run the program from the 

ELECTRONICS Australia, September 1998 


The complete schematic. The BASIC Stamp plugs into SKT1, while SKT2 is used to download its program from a PC. 

beginning. Pins P2, P3 and P4 are used as 
inputs to read the setting of SW2, the Mode 
Select switch. This is a three-way rotary or 
slide switch. These inputs are normally held 
at logic low by the pull-down resistors R2 to 
R4. The switch connects the selected input to 
the +5V line (from the Stamp’s internal reg¬ 
ulator), taking it to logical high. 

The switch we used for SW2 in the proto¬ 
type is a double-pole switch. It is feasible to 
use the other half of this to switch on addi¬ 
tional LEDs to indicate which mode has 
been selected, if you wish. 

The output to the monitor board (located 
in the living room) is switched by MOSFET 
Ql, controlled by the output from pin P7. 
Only a twisted pair of ordinary light-duty 
cable (hook-up wire) is required to link the 
monitor board to the main board. There are 
two spare pins available (P5 and P6) so it 
would be possible to program more elabo¬ 
rate warnings — for example to allow the 
AWD and LED2 to be controlled individual¬ 
ly, but this entails having a cable of three or 
more wires, which is more expensive. 

Sound is picked up by the microphone 
(MIC1) placed near baby’s cot. A cheap 
crystal microphone insert is all that is need¬ 
ed, as we are not concerned about high 
fidelity. The output from this is fed to an 
operational amplifier (IC2) wired as a high- 
gain inverting amplifier. The gain is 
adjustable by means of VR1. 

You could use a rotary pot for this, 
mounted on the front panel of the enclosure 
and provided with a knob. In practice the set¬ 
ting initially made is usually good enough 
for permanent use, so a trimpot on the circuit 
board does just as well. This also has the 
advantage that it is inaccessible, so the sen¬ 
sitivity can’t be accidentally turned down. 

The alternating output from the op-amp is 
rectified by the two diodes D1 and D2, con¬ 
nected as a ‘diode pump’. Each time the out¬ 
put goes positive, current flows through D3 
and increases the charge on Cl. D2 prevents 
the charge falling when the output goes nega¬ 
tive. In a few oscillations the charge is pumped 
up to a level sufficient to trigger the alarm. 

The charge leaks slowly away from Cl 
through VR2, which is set to give a level a 
little below 2.5V. This it equivalent to a log¬ 
ical low at the input to the set/reset flip-flop 
formed by the two cross-connected NOR 
gates. The other input to the flip-flop (IC1, 
pin 2) is held low by the output from pin PO 
of the Stamp. In this condition there is a low 
output from the flip-flop at pin 3, fed to 
Stamp pin PI, programmed as an input. 

When a sound is detected the voltage at the 
wiper of VR2 rises above 2.5V and counts as 
a high input to the flip-flop. This sets it, and 
its output to PI goes high. This can be read 
by the program, after which a low pulse at PO 
is used to reset the flip-flop. The Stamp con¬ 
tinually reads the input at PI, and when a 
high input is received it records that fact and, 
if appropriate, sounds the alarm. 


The circuit is best housed in a small plastic 
enclosure (jiffy box). If you are powering the 
circuit from a battery, use a box big enough 
to hold the battery as well as the main board. 
Mount a power ON/OFF switch on the front 
of the enclosure. 

Of the components on the main board, 
only the reset button SW1 needs to be acces¬ 
sible. You may be able to mount the board so 
that this can be reached through a hole cut in 
the front of the enclosure. LED1 must also 
be visible. As mentioned above, VR1 and 

VR2 could also be mounted on the enclo¬ 
sure. The Mode Select switch SW2 also 
needs to be mounted on the enclosure. 

You could provide mounted sockets for 
connecting the lead joining the main unit to 
the monitor and to the microphone, but we 
prefer a soldered connection as this is less 
likely to become unplugged. If you are able 
to locate the main unit close to the head of 
the cot, the microphone could be mounted on 
the enclosure. Coaxial cable is used to con¬ 
nect the microphone to avoid pick-up of 
electromagnetic interference. The sheath of 
the cable is connected at one end to the OV 
rail of the board and at the other end to the 
metal case of the microphone. 

The monitor board is mounted in any con¬ 
veniently small plastic box, with apertures 
for the sound and light to emerge. 

When assembling the circuit note, that the 
strips are cut in several places. In particular 
note that there are NO cuts at HI5, LI5 and 
M15 underneath IC1. Also note the solder blob 
joining pins 5, 6 and 7 of the socket of IC1. 

Testing it 

The sound input interface is best tested 
before inserting the Stamp in its socket. Use 
a short length of wire to link sockets 1 and 5 
of SKT1; this provides a 6V supply for pow¬ 
ering the ICs. In the same way, link socket 7 
(PO) with socket 2 (OV) to ground the reset 
input of the flip-flop. Use a test meter to 
measure the voltage at the wiper of VR2. 
This should be between 2V and 2.5V. Adjust 
VR2, if necessary, to obtain this. Set VR1 
about midway along its track. 

Now make a noise reasonably close to the 
microphone. The microphone is most sensi¬ 
tive to high-pitched shrieks and cries but, if 
you are too embarrassed to make baby-nois- 

ELECTRONICS Australia, September 1998 


Construction Project 

Intelligent Baby Alarm 

Fig.2: The parts placement/wiring 
diagrams for the two stripboards used 
in the Baby Minder, plus the way a 
* three-position slider switch is used. 


D 1 2 3 4 5 6 7 8 9 10 11 12 13 U 15 

5 V 


es, or when your family gets fed-up with the 
hullabaloo, clap your hands or flick your fin¬ 
gers instead. Such transitory sounds may be 
over too quickly with a moving-coil meter, 
but a digital meter will flash up some values 
exceeding 2.5V. Measure the voltage at IC1 
pin 3; it should be 6V. 

Now reset the flip-flop by briefly connect¬ 
ing socket 7 to +6V. The voltage at pin 3 
should have changed to 0V. Try setting and 
resetting the flip-flop this way several times 
to confirm that it works reliably. 

Test program 

With the Stamp in its socket (right way 
round as indicated by the pin numbers ‘1’ 
and ‘14’ in Fig.2), and the programming lead 
connected to the PC, switch on the 6V sup¬ 
ply. The marked side of the programming 
lead socket goes to the end of SK.T2 marked 
with a double-chevron in Fig.2. 

Run the Stamp program on the PC. 
Usually the first thing that happens is that the 
alarm starts to sound. To get this under con¬ 
trol, type in the beginning of the first test 

high 7 
pause 1000 
low 7 

This causes a high output from pin 7, lasting 
one second. The alarm sounds for one sec¬ 
ond and is then silent. Now type in the rest of 
the program: 

high 7 
pause 1000 
low 7 
input 2 
debug #pin2 
pause 100 
goto readit 

This is for testing the Mode Select switch. 


ELECTRONICS Australia, September 1998 

A closeup of the author’s main stripboard, with the BASIC Stamp module visible 
just left of centre. 

With the switch in position 1, the debug 
command produces a series of ones on the 
screen. Switching to positions 2 or 3 gives a 
series of zeros. Edit the 6th and 7th lines of 
the program to test positions 2 and 3 in the 
same way. Now test the flip-flop action, 
using Testit2: 

high 7 
pause 1000 
low 7 
low 0 

debug #pinl 
high 0 
low 0 

debug #pinl 

The initial one-second beep from the AWD 
triggers the flip-flop (normally the AWD is in 
another room, so it doesn’t trigger the sys¬ 
tem). The ‘low O' puts the reset at zero, which 
does not affect the flip-flop. The first debug 
displays a ‘ 1\ showing that the flip-flop is set 
(by the bleep). The high 0 followed by low 0 
resets the flip-flop and the second debug dis¬ 
plays 0, showing that this has been done. 

If you amend the first line to ‘low 7’ there 
is no sound from the bleeper and both 
debugs give a 0. Also try making a noise 
(clap etc) during the initial 1-second of 
silence, to obtain 1 followed by 0. This com¬ 
pletes the testing. 


The program given in Fig.3, together with its 
flow chart, illustrates the main features that 
an intelligent baby alarm might have, but 
there is plenty of scope for you to modify it 
and add your own facilities. The program 
occupies about two-thirds of Stamp’s mem¬ 
ory, so there is enough room to spare for a 
few more routines. 

We have left two of the Stamp’s pins 
unused, so there is the possibility of interfac¬ 
ing additional circuitry. 

The program begins by turning on the 
beeper for one second. This confirms that 
the program is running and also that the 
electrical connection to the monitor board is 
intact. Then we put the Stamp to sleep for 
two minutes (if only baby would go to sleep 
so obediently, there would be no need for an 
alarm!); this is to give you time to say your 
goodnights and get out of the nursery, and 
for baby to settle down. After that, the pro¬ 
gram resets the flip-flop and reads the mode 
select switch. This sends it to one of three 
routines called ‘one’, ‘two’ and Three 1’. 

Routine 1 is the Immediate mode, which 
sounds the alarm as soon as any sound is 
detected. You might want to use this if baby 
is sick. The Stamp reads the flip-flop output 
continuously and, as soon as it goes high, 
jumps to the alarm routine. There is no way 
back from this; it loops round a circle of 
commands, producing five short beeps every 
20 seconds until you go to the nursery, 
attend to baby and reset the program. 

Routine 2 is the Normal mode, which 
waits until a specified number of sounds 
have been detected during a specified period. 
Subroutine Record waits in a loop while 
word wO counts up from 1 to 6000 (this takes 
about 75 seconds). If a sound sets the flip- 
flop during this period, b2 is set to ‘1’. 
Otherwise it remains ‘O’. The subroutine 
adds the latest value of b2 to the values in the 
other registers b3 to b9, and so obtains (in 
blO) the number of sounds detected during 
the previous 10 minutes. 

If you want a shorter period, reduce the 
number of repetitions of the loop (for exam¬ 
ple ‘for w0=l to 2000’). If the number 


Program Listing 

high 7 

pause 1000 
low 7 
sleep 120 
high 0 
low 0 

bO=pins & 28 

if b0=16 then threel 

if b0=8 then two 


high 0 

low 0 

pause 2 


if b0=0 then one 
goto alarm 

gosub record 

if bl0>3 then alarm 

gosub shift 

goto two 



three 2: 

gosub record 

if bl0>2 then alarm 

if bl0>0 then skipl 



if bl0=0 then skip2 



if bll=20 then OK 
gosub shift 
goto three2 

for bO=l to 5 
high 7 
pause 200 
low 7 

pause 200 

sleep 20 
goto alarm 
high 0 
low 0 

for wO=l to 6000 










for bll=l to 3 
high 7 
pause 50 
low 7 

pause 100 
high 7 
pause 300 
low 7 

pause 100 



goto continue 

ELECTRONICS Australia, September 1998 


RfcAUtht INFO NO.20 

Construction Project 

Intelligent Baby Alarm 


returned in blO exceeds 3 (more than three 
sounds during the last 10 minutes), there is a 
jump to the alarm routine and the action (for 
the program and you) is as before. 

You can alter the ‘if b 10>3’ line to anoth¬ 
er value if you prefer. If the number of 
sounds has not reached the triggering limit, 
the values in B2 to B9 are shifted along, so 
that the value currently in b9 is lost (a sound 
made 10 minutes ago is ‘forgotten’, and b2 is 
copied to b3, ready to put a new value into 
b2 the next time round). 

Routine 3 is the OK mode. It has the 
same alarm-triggering features as the 
Normal mode, but takes a more positive 
viewpoint by letting you know if baby is 
sleeping calmly. Information about this is 
stored in bl 1, which is set to zero at the 
beginning of the routine. 

In our version of the routine we trigger 
the alarm after two sounds, but you can 
use three as before or any other number. 
Each time round the routine, bl 1 is incre¬ 
mented by 1 if no sounds have been detect¬ 
ed; if a sound has been detected, bll is 
reset to 0. When bl 1 reaches 20 (meaning 
25 minutes without a sound) the bleeper 
makes a reassuring ‘de-dah-de-dah-de- 
dah’ signal, but only once. After resetting 
bll to 0, the program continues monitor¬ 
ing sounds as before. 


(All 5%, 0.25W) 

R1 330 ohm 

R2-4, R9 10k 

R5 100 ohm 

R6 4.7M 

R7, 8 lk 

VR1 2M trimpot 

VR2 1M trimpot 

Cl InF greencap 

LEDl, 2 LED, red 

Dl, 2 1N4148 silicon diode 

IC1 4001 CMOS quad 2-input NOR 


IC2 TL081C JFET op-amp 

Q1 VN10KM or similar N-channel 



Stamp BS1 (or Counterfeit) module, with 
software and programming lead. 

MIC1 Crystal mic insert or other crystal 

Operating it 

The operation of the Intelligent Baby Minder 
is really very straightforward, and can be 
summarised in four steps; 

1. Switch on, listen for the initial one-second 
beep, and select the mode you want. 

2. Put baby in cot, press reset button, leave 
the nursery. 



Pushbutton switch (PCB mount 
SPST momentary) 


Miniature PCB mount DP3T slide 
switch (or rotary) 


Three-pin header, straight (buy 40- 
pin and cut to length) 


14-pin header sockets (buy 40-pin 
and cut to length) 

Piezo audible warning device, PCB mount, 3-16V 
DC, 75mm pin spacing; 14-pin DIL socket; 16- 
pin DIL socket; single core shielded audio cable; 
stripboard 40mm x 81mm (15 strips x 31 
holes), and approx 28mm x 40mm (11 strips x 
15 holes); 12 x 1mm terminal pins; plastic 
enclosures for main unit and monitor; Battery 
clip/battery box/mains plug-pack. 

NOTE: The BASIC Stamp BS1 and Counterfeit 
modules are both available from MicroZed 
Computers, of PO Box 634, Armidale NSW 2350. 
Phone (067) 72 2777 or fax (067) 72 8987. 

Their Web site is at, or you 
can e-mail them at 

3. A five-fold beep (and flash) repeated 
every 20 seconds indicates that baby needs 
attention. When baby has been re-settled 
again, press the reset button to re-start the 

4. If you are using OK mode, a ‘de-dah’ 
beep (and flash) tells you that baby is peace¬ 
fully asleep. Enjoy the TV and pizza! ❖ 



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□ Staged concurrently with AUTOMATE Australia’s leading manufacturing technology exhibition. 

The 10th Australian International Electrical & Electronics Industries Exhibition 

Melbourne Exhibition Centre 6-9 October 1998 

• Tues 10am-6pm • Wed 10am-6pm • Thurs 12 noon-9pm /LATE NIGHT / • Fri 10am-4pm 

Australian Exhibition Services Pty Ltd 424 St Kilda Road Melbourne Victoria 3004 Australia Tel +61 3 9261 4500 Fax +61 3 9261 4545 E-mail: cocklemo? 


ELECTRONICS Australia, September 1998 


• Quality construction kits, manufactured in Germany, with two year warranty. • Three computer controlled kits available; Profi Computing 
kit (builds 12 models), Turtle kit and Mobile Robots Kit. • Software, ready to run, is provided for DOS and Windows. Source code in BASIC, 
C, Pascal, Delphi and VisualBASIC for windows allows you to modify existing programs or write your own programs. LLWIN a new flow¬ 
chart language - ideal for machine control - is now available on CD-ROM, PC-LOGO from Harvard Associates with robotic commands is 
also in stock. • Two interface units are available, one plugs into the IBM-PC printer port the other ‘intelligent’ interface plugs into the ser¬ 
ial port. Each provides eight on/off inputs, four forward and reverse motor outputs and two analogue inputs for position, pressure, light 
and temperature sensing. The number of inputs and outputs may be expanded on both units. The new ‘intelligent’ interface has an inbuilt 
microcomputer and operates from batteries giving your models complete mobile freedom! The interfaces and software may be purchased 
separately. • Non-computer controlled kits are also available, including; I’m Walking a bionics kit, Cartech, Pneumatics and new Solar kit 
(from $149). • Fischertechnik is recommended by Steve Cremer - winner of the US presidential award for science teaching. 

Available From : PROCON TECHNOLOGY Tel (03) 9807 5660 Fax (03) 9807 8220 
PO Box 655 Mt Waverley, VIC 3149 Email : 

VISA, MC, BC Accepted. For more pictures & free software see Web site : http://www1 


T raffic jams! Aren’tya sickathem? 
Everywhere you go nowadays, you 
seem to be not going at all, but sitting 
there in your car waiting to move forward a 
few metres. Or when you do move, it can get 
downright scary. 

My home, nowadays in Port Townsend, 
Washington, shouldn’t have traffic jams, 
because its population is only 8000 people. 
As well, Port Townsend is at the end of the 
road; it’s not on the way to anywhere, 
because it’s located on a peninsula and is 
surrounded on three sides by the sea. So traf¬ 
fic goes to Port Townsend, stops, turns 
around, and goes away again. 

The cars per unit of road are not many — 
but still, everything is slow. For one thing, 
speed limits are ridiculously slow — such as 
40km/h along a big wide highway that 
would be 80km/h in Australia. 

Add to this the town’s large pop¬ 
ulation of senior citizens, and 
suddenly things are moving very 
slowly indeed. 

There are categories into 
which drivers may be placed, in 
descending order of speed of 
travel (please pardon lapses of 
political correctness here...): 

0: A normal, uninhibited driver. 

(See photo, a sign on my own 

1: The driver of a large 
American sedan — Buick, Oldsmobile, etc. 
2: Sedan driver with headlights on in the 
daytime, for ‘safety’. 

3: Sedan with lights on, driven by an old 
man wearing a hat. 

4: As in 3, with wife in back seat. 

There are further categories of course, spe¬ 
cific to Australia: 

5: Car displaying bowling hat on back parcel 

6: Car driven by old lady wearing bowling 

7: Car with four old ladies wearing bowling 

8: A hearse. 

Seattle, Washington (not far from my 
home) has what’s considered the worst traffic 
for a city its size in the USA. Like so many 

American cities, Seattle is blessed (or plagued, 
depending on your point of view) with free¬ 
ways, part of the interstate highway system. 
And these might not be free much longer... 

These super-roads bisect many cities up 
and down, left and right. In Seattle’s case 
Interstate 5 (1-5) runs north and south along 
the city’s backbone. About midway along, I- 
90 runs east and west. Another freeway 
known as 405 runs through Seattle diagonal¬ 
ly. These roads are sources of great frustra¬ 
tion, and sometimes great adventure. 

During non-peak times, there is plenty of 
traffic, but it flows freely — very freely. There 
is a speed limit of lOOkm/h, which means 
everybody goes at 140, except when there is a 
cop around. The freeways carry anything up to 
five lanes in each direction, and they are filled 
with semitrailers as well as cars. 

So sometimes you’re barreling along with 
the flow of traffic, with one semi behind you, 
one in front and one on each side, all moving 
as a mass at 140km/h. If the truck at your left 
decides he wants to be in your lane, he will 
signal, blast his air horn, and then begin 
merging right. Your job is to apply the brakes 
in such a way as to be out of his way when he 
begins to occupy your space — while not 
being rear-ended by the semi behind you. 

For us country bumpkins, a trip to the big 
smoke is a trying time indeed. Imagine what 
it’s like then, when the above-described 
mass of moving metal comes upon a Type 3 
driver chugging along in the centre lane at 
50km/h. That’s Seattle traffic, and there are 
many prangs every day, all dutifully 
announced on radio traffic reports by over¬ 

head aircraft. 

Most of my trips to Seattle have been to 
pick up or drop off someone at the airport. 
This involves a trip of more than 160km, 
along both shores of Puget Sound. To be 
sure of getting to the airport by the required 
time, one must allow three hours, although a 
really good run can take only half that. 

Along the west side (my side), it’s usually 
fairly easy sailing until you get to the place 
where you actually cross Puget Sound — the 
Tacoma Narrows. Here there’s a big suspen¬ 
sion bridge which is world famous because 
of some film of it taken during a storm. The 
wind got the whole bridge vibrating at its 
resonant frequency, and the film showed it 
twisting violently back and forth, merrily 
tossing cars about. 

The bridge has been redesigned now, with 
its resonance damped. But it’s 
still fun to collect some new 
arrival at the airport, and then 
when exactly the right moment 
comes, you say, “Remember that 
TV film of a bridge twisting and 
bucking? Well, you’re sitting 
right in the middle of it!” 

There are still people living in 
the Seattle area who to this very 
day refuse to go anywhere near 
the Tacoma Narrows bridge — 
they take the ferries instead, at 
great expense and at risk of late 
arrival due to overcrowding. 

I mention the Tacoma Narrows bridge 
because it is the traffic jam champion of the 
Pacific Northwest. The bridge has two lanes 
in each direction; you’d think that would be 
enough. But when traffic hits that bridge it 
slows to a fraction of normal speed. Maybe 
that’s because drivers are afraid of starting it 
shaking again. 

Once cars are on the other side they start 
moving properly again. But for cars on the 
input end of the bridge, traffic comes to a 
start/stop standstill, and in peak hour this can 
extend up to 20km each side of the bridge. 
And if there’s a prang on the bridge 
ooohh! That’s why you have to allow three 
hours to get to the airport. 

These are big problems for traffic planners. 

“If the truck on your left decides he wants to 
be in your lane... your job is to apply the 
brakes in such a way as to be out of his 
way when he begins to occupy your space 
— while not being rear ended by the semi 
behind you.” 


ELECTRONICS Australia, September 1998 

There’s already a scheme to build a second 
bridge next to the Tacoma Narrows bridge, or 
perhaps a second deck on the main bridge, to 
ease traffic flow. But the roads feeding into 
each end of the bridge are two lanes each 
way; the bridge itself has two lanes each way. 
How is doubling the lanes across the bridge 
going to make any difference? If drivers are 
still afraid of the thing collapsing, they will 
still go slow. And the current plan is to slap a 
toll on the bridge to pay for its expansion, 
making it just as expensive to use the bridge 
as to take the ferries. 

Now traffic planners are starting to 
realize that traffic congestion can’t be 
solved by simply building more 
roads, because traffic always seems to 
increase to fill whatever roads are 
available. Instead they are starting to 
find ways to make the most efficient 
use of what’s already there. 

Traffic authorities in Seattle, and 
some other cities, are already using 
lanes called ‘HOV’ lanes (high 
occupancy vehicle) on 1-5. These 
are usually the innermost lanes, set 
aside for cars with at least two peo¬ 
ple in them, and buses. At the same 
time, trucks may be limited to the 
two outside lanes, so the speed of traffic 
follows a gradient from the outside to the 
inside lanes. 

However, since most cars particularly at 
peak hour contain only the driver, the HOV 
lanes are badly underused and therefore not 
really efficient. But the going is certainly 
good for those who DO use the HOV lanes, 
except for one stretch of 1-5 where the HOV 
lane has two wheels on concrete, and the 
other two wheels on bitumen. It’s a strange, 
and worrying, way to travel. 

Now clever traffic engineers are working 
out ways to make more efficient use of HOV 
lanes. This involves declaring HOT (high 
occupancy toll) lanes, the idea is to let multi¬ 
person cars use the lanes as normal, but also 
allow solo drivers to use the lanes — at a price. 
A toll will be charged, low enough to encour¬ 
age efficient filling of the fast lanes, but high 
enough to keep them from getting jammed. 

The idea is to keep a fairly constant flow 
going in the HOT lanes, regardless of whether 
or not it is peak hour. So it’s intended to vary 
the HOT lane toll dynamically, depending on 
the time of day and measured traffic volume. 
The problem is that you can’t very well stop 
every car to collect the toll; that would pro¬ 
duce more, rather than less, congestion. 

So — electronics to the rescue! Every dri¬ 
ver who intends to use the express lanes will 
be set up with a special account. His car will 

be equipped with a small transponder which 
sticks to their windscreen with Velcro. As a 
driver approaches the start of an express 
lane, there will be an electronic sign advising 
the current price. This might vary from SI .50 
when the lanes are wide open, up to $4.00 at 
peak hour. As the car progresses along the 
express lane, radio equipment interrogates 
the transponder, taking note of its account 
number. Then the toll can be automatically 
extracted from the driver’s Visa or 

Tom emailed us this pic of his current 
car’s number plate, with its surround 
message neatly summarising his feel¬ 
ing about driving conditions... 

This system is already being used in San 
Diego, California, from the beginning of 
April this year. When transponders came on 
the market, the initial 1600 were snapped up 
in the first week. Now there are more than 
2500 in use, and that number is expected to 
double before long. 

Knowing the capabilities of the electron¬ 
ics in this system, it’s possible to think of 
some further refinements. If each transpon¬ 
der were interrogated, say every kilometre, 
and if there were frequent electronic signs, 
then you could encourage drivers to move in 
and out of the express lanes at will. 

If congestion in the express lane becomes 
too heavy, you could raise the toll by fifty 
cents or so, displaying it on the electronic 
signs. A certain proportion of drivers would 
decide it wasn’t worth it and move to slower 
lanes. Then the transponder would disappear 
from that lane, and toll charging would stop. 
If express-lane traffic decreased, the toll 
could be lowered and cheapskate drivers 
would move back into the express lane. 

Since transponders would be interrogated 
periodically, it shouldn’t be too difficult to 
measure the amount of time drivers spend in 

the express lanes and charge accordingly. If 
they’re paying by the minute, it would 
encourage everyone to go the speed limit 
instead of dawdling. And, if someone was 
speeding, the system could compare time 
versus distance covered and whack him with 
a mail-order speeding ticket. 

This dynamic-pricing system sounds 
attractive, but in practice, how much con¬ 
gestion could it actually relieve? According 
to John Semmens of the Arizona 
Department of Transportation, you’d have 
to convert the entire road system onto 
dynamic pricing. But if that could be 
achieved, overall congestion could be 
reduced by 10%, fifty times as much as 
a light-rail system might eliminate. 
And it would be 140 times as cost- 
effective as rail, says Semmens. 

There are, of course, social concerns 
here. It’s felt that the system would dis¬ 
criminate against less well-to-do drivers 
who could not afford the tolls (they’re 
calling the new express lanes ‘Lexus 
Lanes’). But even then, less prosperous 
drivers would still benefit from less 
congestion in the ‘Peon Lanes’ as the 
Lexi moved into the express lanes. 

Is this plan useful in Australia? 
That’s hard to say. I’ve seen some whop¬ 
per traffic jams in Oz, especially when I 
was living in Melbourne. But they don’t 
hold a candle to the horror that happens 
daily in Seattle.... 

Still, this might give you some ideas to 
discuss with your local politician as you sit 
there tapping your toe, waiting for traffic to 
start moving again. ♦> 




• Unrivalled performance-exceptional value at just $59 

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0 NetCraft 


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Bankcard Mastercard & VISA 
Overnight nationwide delivery on most orders 
NetCraft Australia has the complete range of Red Hat products 
including the Applixware Office Suite, Books, 

T-shirts and morel 

ELECTRONICS Australia, September 1998 




earning II? 

You will be amazed with the incredible realism of your favourite 
music tracks with these fantastic C 3300 D.I.Y. Home Theatre 
Loudspeaker Kits! This month we have also introduced a new 70W 
IRODA GAS Irons PLUS the new feature packed A 1200 Bike 
Computer has just arrived! I urge you to place your order promptly, 
as many of the items are in high demand and will not last at these 
prices. Remember our EXPRESS JET SERVICE will deliver your 
order FAST! 

(Country areas please allow 
an additional 24*48 hours) 

Remote Control 

, ^ This learning remote control can 

fflv replace up to eight remote 
IB controls! Featuring: • 8 Appliance 
V Modes • 2 Auxiliary Modes 
IB • Intelligent Backlighting - Once 

I--Activated, dims away 

Get rid Of your after being idle for 5 
Coffee table remote seconds, saving batteries! 
clutter with this (Unlike others on the 
amazing unit! market) Requires 4 x AAA 

-1 batteries (supplied). See 

97198 Cat. pl70 

A 1000 Normally $ 199 , NOW $-1 69 

Best Regards, 

Jack O’Donnell, Managing Director 

Hi-Fi & Home Theatre Loudspeaker Kit 

"They sound great with any music from K 
classic to rock, from Mozart to Metallica/'^fi 

Leo Simpson , Silicon Chip Magazine 
Designed by acclaimed Australian loudspeaker designer 
Richard Priddle, these speakers are engineered to deliver superb 
sound quality whilst being incredibly simple to assemble. 

• Enclosures. The cabinets are precision crafted on CNC machinery from 
high quality MDF material, and feature a new and simple construction 
method which provides incredible joint integrity. Each panel is cut with 
close-tolerance precision to ensure the enclosures fit together as designed, 
without leaving unsightly overhangs, leaking air gaps or mis-matched 
veneer. All driver, port and terminal holes are pre-cut and recessed. Speaker 
grille is pre-covered in acoustic cloth ready to fit. 

• Drivers. The loudspeakers feature our new series of polypropylene hi-fi 
drivers, exclusive to Altronics in Australia. The 6.5" woofers produce deep, 
punchy bass and maintain their response through the mid-frequencies to 
provide a linearity of response most two-way systems cannot hope to 
reproduce. The fabric dome tweeter handles the most demanding of top-end 
program with ease, producing crisp, clean highs and exquisite detail. 

• Crossovers. The crossover has been computer-optimised to deliver the 
best sound quality when coupled with these drivers and enclosure. It uses 
high quality capacitors and low-impedance inductors to minimise signal 
colouration and phase-error. 

• Kit Components. The kit includes flat-packed cabinets, drivers, 
crossover components, terminals, speaker wire, port tube, acoustic wadding 
and detailed assembly instructions. In fact, all you need except a bottle of PVA 

FEATURES: • No electronics expertise required. Simple step-by-step 
assembly instructions included. ■ No special tools required, all HflRl 

sections are pre-cut and machined. Typical assembly time 2 to 3 
hours. • Fully pre-assembled 2nd order, impedance matched 
crossover. HjjMB 

• Everything supplied, all you will need is PVA adhesive. 

plus delivery j 

LCD Bike Computer 

This compact bike computer f~ 

is a must for serious »■■ ■■ ■ 1 _- 

cyclists! It has all the 

standard features ftJBBBBB|pBB\ 

you’d expect PLUS UM •O' ®; 

for added security 

you can simply 

detach it from the 

bike and put it in 

your pocket once j 


• Current Speed • Average Speed H 

• Maximum Speed • Trip Time S 

• Trip Distance • Total Distance 

(Odometer) • 24Hr Clock Time • Countdown Timer 

• Countdown Distance. Supplied with mounting 
brackets, magnetic pickup, spoke magnet, even the 
battery! (Valued at $3.95) 

A 1200 Normally $37.95 NOW$ 2 9 -95 

C 3300 Complete Kit 

plus delivery 

CA3300 Kit(Less Cabinet) 

CB3300 Cabinets Only 4^. ^7 

Delivery Fee of $25 applies to C 3300 and 
$12.50 applies to CA3300 & CB3300 

plus delivery 

Gas Powered 



Keychain Model. This laser pointer weighs only 
45g, with batteries, and comes complete with a keychain." 1 
Measuring only 61mm long by 14mm in diameter, it s not 
much bigger than many keys! It emits a very intense 
beam that can travel up to 50m, and projects a — 
bright red dot onto the target is it aimed at. It's 
ideal for lectures, guided tours, seminars, building 
sites etc, and it's much less intrusive than a normal 
stick pointer! Uses two button batteries (included). 

A 0201 Normally $69, NOW ONLY $35 

The advanced IRODA Soldering Iron offers 
go-anywhere soldering convenience. It features a thumbwheel 
heat control, cap mounted igniter, long life catalyst tips and a 
huge gas reservoir for long use-time. The kit consists of the 
IRODA Gas Soldering Iron supplied in a handy carry case 
y with a range of tips and accessories. 

\ Features: • See-through gas chamber • Igniter built 
— j into cap • Uses standard butane gas • Supplied with 

safety stand, cleaning sponge, solder dispenser, blow 
torch, hot air blower and hot knife cutter 


Whereas we are unaware of any of our customers (being principally engineers and electronic enthusiasts) 
irresponsibly using laser products, pointing towards the eye of any human or animal could cause eye damage 
and lead to criminal charges. Altronics is limiting the power output rating of all new stocks to lmW. Current 
stocks (approx. 3mW) are not available to persons under 18 years of age and are sold on the strict 
understanding they will not be left where they could fall into the hands of juveniles or irresponsible persons. 

T 2592 Complete Kit with Accessories, will retail for $89 9S 
T 2590 Gas Iron plus Blow Torch Tip, will retail for $49 95 


SaiRSlW The first 100 callers Jo 

purchase either a T 2592 or T 2590 qualify for our FREEbonus 
offer of a roll of T 1100A solder and a T 2447 Butane Refill, 
tooether valued at $12.95 MIES®@lL(U>YlBtL V Ir-lfSlkLsB _ 

Pen Model. This stylish slimline laser pointer is housed in a sturdy metal 

case about the same size as a fountain pen, and includes a pocket 

clip. Ideal for lectures, guided tours, seminars, even 

building sites, and its much less intrusive 

than a normal stick pointer! Push-to- 

activate operation. Uses two AAA cells 

(included!). Supplied with soft 

leatherette storage case. 

A 0200 Normally $99, NOW $49 

Exclusive to 
Altronics and 

Micro Jet Blow Torch 

Powered by a refillable gas 
lighter (supplied), tins blow ,, . 

torch burns at 1300’C. 
making it Ideal for all types ot 
brazing and heavy duty 
soldering It can bo ignited and 
used with one hand, and the in¬ 
built piezo electronic Ignition 
ensures easy lighting every time 

Ideal tor the workshop, _ 

lool box, work bench 

etc. ■■■■ 

T 2490 WAS $24.95, 

“Virtually anyone can construct these 
speakers, whether they have wood-working 
skills or not. No special tools are required, 
although you will need a bottle of PVA glue. 
Once assembled, you will have a set of 
speakers you can really be proud of. In my 
opinion, these are comparable to speaker 
systems costing $1000 or more. In fact, they 
look and sound so good, your friends will 
not believe you built them yourself. 

Leo Simpson, Silicon Chip Magazine 

1 -800 999 007 PERTH (08)93281599 


Central Door 
Locking Kit 

All four doors will automatically lock or 
unlock with the operation of either of the 
front doors. Add the ease and convenience 
of central locking to your car. Can be interfaced to 
our S 5205 car alarm (and others) to lock or unlock 
all four doors when the alarm is remotely armed or 
disarmed. Kit includes everything you need to fit 
central power locking to your vehicle; module, solenoids, rods & couplers, 
grommets, punched strip, screws & clip nuts, even the wiring harness! The 
actuators are motorised with an inbuilt gearbox to ensure reliable and positive 
operation. One actuator is mounted inside each door. Includes central control 
unit which mounts under the car dash. For use with 12V negative earth systems. 

S 5241 Normally $119 ea, NOW A CRAZY $69 


Stock, Be Quick! 

/Not available from dealers) 

TITAN Remote 
Car Alarm 

Purchase both the 
S 5205 and S 5241 for just 
$229 for the set! 

Don’t let car thieves make off with your 
pride and joy, install one of these 
security systems and save $$$ on 
comparable units. 

Secure your vehicle with this versatile 
TITAN car security system.System kit 
includes alarm module, two remote 
controls, battery backup siren, shock sensor, 
valet switch, status LED, wiring harness 
and hardware. Features: • Two remote 
controls • Super Loud 127dB siren 

• Remote panic • Battery backup and 
tamper proof siren • Child proofing and 
anti intrusion alert while driving • User selectable exit 
delay and auto re-arming • User selectable arming/disarming chirp 

• Starter kill • Valet mode • Automatic shunt of defective entry zone • Alarm 
memory indicates which zone (1-3) triggered • 60 second siren with auto reset 

• Two colour LED indicator • Can be interfaced with central locking (where 
fitted) • 3 extra channels on remote to control features such as boot release, etc. 

S 5205 Normally $229, NOW $1 69 

Desoldering Tool ”■* 

Easily desolders a 14pln 1C In around 30 seconds. Once desoldered, ih * 
component virtually falls out! 

The T 1280 MICRON SURE SHOT Desoldering Tool makes it a breeze to 
remove components from any PCB, even double sided, through-hole plated 
boards. All it needs is a squeeze or two on the trigger and the component 
virtually falls out. Features: • Totally self contained • Light and compact 

• Anti static tip • Safe & easy to use • Simple to clean and 
maintain • Variable tip temperature. 

hii'ul far service techs , manufactur ers, R &D centres, enthusiasts. 

T 1280 Was $349 NOW ONLY $299 
T 1282 1.0mm Replacement Tip $34.95 
T 1283 1.6mm Replacement Tip $34.95 

30W Variable Tempi 

Soldering Iron 

Tip temperature is adjustable from 
250°C to 450°C. Select the right 
temperature for the job and 
avoid heat damage to sensitive 
devices! Features ceramic 
heating element and supplied 
with 1.6mm conical tip. 3 other tip 
sizes available. See 1997/98 Catalogue pill. 

T 2446 Normally $55, NOW $49 

Micron Soldering Station 


Electronic Temperature Controlled Soldering Station 
The ultimate in controlled temperature hand soldering for hobbyist and 
professional applications. Features • Huge 60 watt heavy duty element 

• Dial up temperature control with ±1°C stability at idle • Temperature 
range 250°C to 450°C • Ceramic heater element with embedded 
thermocouple for ultra-fast heat recovery • Zero voltage switching to 
minimise voltage spikes at tip • Low voltage element for added safety • Built in 
sponge tray with tip cleaning sponge • Full range of replacement long-life tips 
available • CMOS-safe grounded tip 

T 2441 Normally $199, NOW $1 29 

UpTeK Professional Digital Multimeters 

Altronics has been appointed Australian distributor for this fine range of UpTeK digital 
multimeters. These superb meters are ideal for the hobbyist and professional alike. All feature UL 
approved fuse protection on current inputs, large high contrast 3.5 digit LCD displays, high 
quality instrument leads, built-in stand and rugged construction. If you want the best performing 
multimeter for your dollar, then look no further than these excellent instruments. 

All are supplied with high quality, silicon rubber insulated instrument test leads. 

Save a MASSIVE $70! 
Features ceramic element with embedded 
thermo couple for ultra-fast heat recovery. 
Ideal for the hobbyist or professional! 

6 Input Stereo Mixer 

43 Range LCR DMM 

• 20MHz Frequency Counter 

• Incorrect Lead Socket Beeper 

• Peak Hold & Data Hold 

• Auto Power Off 

• Inductance < 2mH - 20H 

• Capacitance < 20nF - 2000pF 

• Frequency < 2kHz - 20MHz 

• AC Volts < 200mV - 750V 

• DC Volts < 200mV - 1000V 

• Resistance < 2000 - 20ML2 

• Continuity Buzzer 

• AC/DC Current < 200pA - 10A 

• TTL/CMOS Logic Tester 

• Diode Check 

Q 1108 $1 39 

Auto Ranging DMM 

• 32 Segment Bar Graph 

• Manual Override of Auto-ranging 

• Incorrect Lead Socket Beeper 

• Range Hold & Data Hold 

• Auto Power Oft 

• AC < 320mV - 750V 

• DC Volts < 320mV -1000VDC 

• Resistance < 3200 - 30MO 

• Continuity Buzzer 

• AC/DC Current < 320pA - 10A 

• TTL/CMOS Logic Tester 

• Diode Check 

Q 1104 

$11 9 

30 Range DMM 

• Temperature -50°C to 1100°C 

• Data Hold 

• Auto Power Off 

• AC Volts < 200mV - 750V 

• DC Volts <200mV- 1000V 

• Resistance < 2000 - 20MO 

• Continuity Buzzer 

• AC/DC Current < 200pA - 10A 

• Diode Check 

Q 1102 $1 09 

Q 1103 Thermocouple $1 5 



TRUE RMS 34 Range DMM 

• True RMS AC measurement to 5kHz 

• Frequency Counter < 2kHz - 20MHz 

• Data Hold 

• Auto Power Off 

• Low Ohms Capability (< 20i2) 

• Zero Adjust on Low Ohms 

• AC < 200mV - 750V 

• DC Volts < 200mV - 1000VDC 

• Resistance < 200 - 20MQ 

• Continuity Buzzer 

• AC/DC Current < 200pA - 10A 

Q1106$1 1 9 

RP M//s MONTH! Purchase any one of these 

carry holster (Q 1115), valued at $12.95, absolutely FREE- 

Great for dubbing videos, multimedia, or as a basic PA 
mixer. Two 6.35mm mic inputs, two RCA stereo line 
inputs, and two RCA stereo phono inputs. Assignable 
headphone monitor, LED output level indicators and two 
stereo outputs. 

A 2540 1998 Price $149, NOW $99 

NiCad Batteries 


NiCads will eventually pay for 
themselves, and can provide 
hundreds of recharges if cycled 
periodically. They can be used in j 
just about any battery powered 


S 4705 700mAh AA Cell Normally $2.50 ea, 

NOW $2 ea, 10 & up, or $1 ' 60 ea, 25 &up 

S 4710 1500mAh C Cell Normally $4.95 ea, 

NOW $4 ea, 4 and up, or $3 50 

ea, 10 & up 

S 4715 1500mAh D Cell Normally $7.25 ea, 

NOW $4 ea, 4 and up, or $3 75 

ea, 10 & up 

S 4720 lOOmAh 9V Cell Normally $12.95 ea, 

NOW $8 ea, 2 and up, or $7' st * ea, 4 & up 

RTH mn\ Q39ft 15QQ 



CLASS A Audio 
Amplifier Kit 

(See Sc July '98) This kit is a must for any serious 
Audiophiles who demand a highly accurate 
reproduction of their favourite music. Class A amplifiers 
typically have peak distortion less than twice the average 
distortion of class AB amplifiers, figures that are almost unmeasurable 
(typically in the order of 0.0005% ). Specifications: • Signal to noise ratio of -115dB (un-weighted) 
and - 119dB (A-weighted) • 15W rms into 8 D • No Crossover Distortion at low power 

K 5109 $49 H 0545 Heatsink to suit $23.95 

K 5110 Regulated Power Supply to suit $26.95 

Motorcycle Helmet Beat 

Intercom Kit Triggered 
Strobe Kit 

Video Fader Kit 

Add professional "IP” 

& fades to your home 

videos'. Even inc ' ude 
an enhancer to boost 
lh e edited signal. 


Allronlca Kit 


(See EA July '98) 
Communication between 
the rider and pillion 
passenger on a motor¬ 
cycle can be difficult when 
you are moving at lOOkph. 
This project allows hands 
free communication 
between the rider and 

passenger of a motorcycle. Features: 

• Separate battery supply (4 x AA) or 
motorcycle system supply • Low & high pass filters 
to reduce vibration & wind noise through the mic 
• VOX on/off • Single volume control for both 
channels • Supplied in an attractive case small 
enough to fit into a jacket pocket. 

K 5270 $45 (Helmet not supplied) 

(See SC Aug '98) 

You've seen these in 
Nightclubs and rock concerts. 

Strobes add super lighting 
effects in darkened entertaining 
area’s. It is sure to add tons of 
life to any party or B.B.Q. Features • Variable rate and 
sensitivity for beat settings • Line source inputs for beat 
triggering • Selectable beat / continuous functions • 
Simplified construction to it's predecessor • Powered 
from a standard 240V mains source • MDF box, carpet, 
robust aluminium reflector (unlike others on the market) 
and all the necessary components for a single strobe 
model. Also available is a second tube option for those 
who need twice the light. 

K 5792 $1 59 

(See EA April '98) 

Got »oiv\e hum# videos you'd like to edit 
properly for keeps? This useful kit allows you to 
add basic professional video effects such as 
horizontal and vertical wipes, fade-ins and fade- 
outs during your editing. Features: • Wipes 
_J horizontal and vertical • Fade or wipe to black or 
white • Supports both BNC or RCA inputs • Built-in 
switchable signal enhancer so you'll maintain a high picture quality during the 
process. You'll be surprised just how professional-looking your results can be 
simply by using this very easy to build kit! Powered by 12VDC plugpack. 

K 5875 $65 M 9660 12VDC 300mA Plugpack $13.50 

12V lnl@[l©gj©tn) Discolight Kit 

(See SC Jan/Feb '98) Based on the 
original Silicon chip 
Discolight, this unit offers 
the same features as the 
mains version only with 
low voltage rails, making it 
ideal as a school project or to 
add something different to your car at the 
next car show or auto salon! Supplied with 
an attractive case with pre-punched and 
screened front panel and parts to build and 
power the unit from 12V DC (halogen 
lamps not supplied). Features: • 4 channels J 
(20W or 50W halogen lamps) • Forward, 

reverse and auto reversing chaser patterns with music modulation • 
Simultaneous strobe on all channels • Alternating light patterns • 12V 
DC or AC operation • Input from loudspeakers, aux level or mic . 

K 5807 Normally $159, NOW $1 09 (Lamps not supplied) 

K 5797 Two Tube 
Option $18.95 

Sound Card Preamp Kit for PCs 

Sustain Unit Kit 

for Electric Guitars 

See SC Apr '98) A sustain 
[unit can make your guitar sound 
little more "live", by keeping 
the volume of a note at a constant 
level while the string resonance dies 
away. It's one of the most widely 
used guitar effects (FX), and this 
Simple kit is a fraction of the cost of a 
commercial unit! It features adjustable attack and 
decay, a defeat switch and standard 6.35mm 
input/output jack sockets. Requires a 12V DC 
power supply. Supplied short form so you can 
build it into a custom case, if required. 

K 5539 $27 95 

Plugpack to suit M 9664 $14.50 

A <lfl r.ufthtin to 

onutiorcinl until 

FM Stereo 
Transmitter Kit 

(See SC Oct '88) 

Simply connect your^ Q 

CD player or any 2? --- 

other line level source l 
to the mini transmitter! ** VUu " 
which converts the 'T n *<* 
audio signal to an FM 
signal. This FM signal can 
then be tuned in via any FM 
radio. Great for listening to 
your favourite CD while washing the car, mowing 
the lawn or doing the vacuuming etc, 
without blasting the neighbours. 

k„20$34- 95 

(See EA August '98) 

There ate many audio 


ind . 

available over the Internet, whlc 
utilise the microphone input of 
your sound card. It attenuates a 
abnormally high signal levels to 
acceptable input levels to your 
sound card. 

Features: • 4 input levels of 
attenuation of +20dB to - 40dB • Presents a 1ML2 
input impedance, the same as offered by a 
professional oscilloscope • Low ohm output 
impedance • Limit indicator to alert the user that the A/D converter of 
your sound card is in over range • Powered through the +5V outlet on the 
joystick port of the sound card (no plugpack required!). 

K 2875 $34 9S 

Transform your PC into 
a fully fledged Audio 

Analyser or CRO whilst 
protecting your sound 
card from damage! 

CRO Probe to suit Q 0175 $39.95 


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Phone (08) 9328 1599, Fax (08) 9328 3487 
MAIL ORDERS C/- P.O. Box 8350 

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I Standard Delivery & Packing Charge: $4.00 to 500gms, $5.50 500gms-l kg, $8.00 lkg-5kg. 
I Where possible we process your order the day received and despatch via Australia Post. 
1 Allow approx 9 days from day you post order to when you receive goods. 

I Overnight JeUervice: Up to 3kg is $9.50, 3kg to 5kg is $16.00—We will process your order 
I the day received (if placed before 2.00PM WST) and despatched for delivery the next day. 
I Country areas please allow an additional 24-48 hours. 








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1-800 999 007 Perth (08)9328 1599 

MO Vs, battery ampere-hour rating & the Y2K issue 

Our topics this month are 
mainly centred around 
batteries and the Y2K 
problem. For example, have 
you ever wondered about the 
ampere-hour rating of cells 
connected in series? We 
answer this and other reader 
enquiries, and present a 
method of testing MOVs 
(metal oxide varistors). 

’m continuing the discussion on the Y2K 
bug this month, with letters from readers 
who are actually involved in programming 
microcontrollers. Last month I discussed the 
issue from a more general aspect, reporting 
on the ‘doom and gloom’ the media typically 
attaches to the topic. 

But what arc the facts? Will aeroplanes 
crash? Will there be a global depression? We 
can’t address these topics as there are too 
many unknowns, but we can look at appli¬ 
ances and equipment that use an embedded 

The first letter is from a reader employed as 
a senior software engineer. He has had consid¬ 
erable experience with microcontrollers, and 
makes the point that cost is the driving factor 
on whether an appliance has a date-dependent 
operating system: 

Your correspondent Nicholas Smith raises 
the question of the infamous and over-hyped 
Year 2000 bug as it relates to common appli¬ 
ances, such as a microwave oven. Mv first 
electronics job in 1986 involved designing 
microcontroller-based systems for white 
goods. With 10,000 units per year represent¬ 
ing a low-volume run, the need for every 
resistor (0.7 cents each) was carefully con¬ 
sidered, as was the need for a real-time 
clock (RTC). 

The micros were 8048s, with 8049s for big¬ 
ger jobs; no sign of an RTC, even though 
many products had a clock display. We imple¬ 
mented clocks as a software driven time-of- 
day counter, but without a date function, as 
adding date-driven code cost too much. 

Therein lies the fundamental point — in 

the embedded micro world, cost is the main 
factor. If it's not absolutely necessary, we 
don 7 spend money or time on it. 

Over the years 1 have been involved with a 
large number of microcontroller-based pro¬ 
jects. Very few incorporated a ‘built-in ’ 
RTC, although later micros do offer them. 
One of these projects included an external 
RTC chip, and it was thoroughly tested to the 
late 21st century, well beyond the expected 
product lifetime. 

Most whitegoods, even though they com¬ 
monly incorporate a time-of-day clock, don 7 
have any date dependence. For that matter, 
about the only product that has date depen¬ 
dence is a VCR. The many micros in cars, TVs, 
washing machines, dishwashers, microwaves, 
ovens, heaters, even kettles (really!) don’t 
know and don 7 care what the date is. At most 
they might care about the time of day. 

It might be an idea to test your VCRs for 
Year 2000 compliance, but for everything 
else I wouldn 7 bother. My opinion is the 
only applications where the Year 2000 issue 
is really important are accounting and other 
financial applications, where time differ¬ 
ences based on dates need to be calculated. 
(Geoff Field B.E. Grad I.E.Aust, Chelsea 
Heights, Vic) 

Thanks Geoff, for acquainting us with the 
‘nuts and bolts’ of appliance design and man¬ 
ufacture, and in particular to the aspect of cost 
on the design. However, while whitegoods 
might not be a problem, 1 wonder about build¬ 
ing management systems that use a microcon¬ 
troller. Are these systems date dependent? 

On the other hand, I also wonder just 
when programmers started realising that the 
year 2000 was just around the comer. I 
would expect most programmers would have 
started writing code to suit 2000 at least from 
the start of the 1990s. 

The next letter is also from a reader involved 
in microcontroller use and programming. 

/ think this Y2K thing is being blown out of 
all proportion, like the virus danger some 
years ago. At the mere suggestion that basic 
appliances might be affected by it, I don 7 
know whether to laugh or cry! 

For over 14 years 1 have been in the busi¬ 
ness of designing and programming micro¬ 

controller systems, mainly for industrial 
applications. I have not yet seen a microcon¬ 
troller chip with an inbuilt clock-calendar 
function. As in a PC, if you want that func¬ 
tion, add an external clock-calendar chip 
(CCC) and a battery to run it. But even then, 
the CCC is just a peripheral of the micro¬ 
controller; it is not in charge of proceedings. 
The in formation from the CCC is used at the 
discretion of the programmer who writes the 
microcontroller code. 

While some appliances (e.g., VCR, 
microwave oven) incorporate a clock, it’s no 
guarantee they have a CCC. Generally they 
don 7 retain time without mains power, so 
it’s likely the time is derived from a mains 
interrupt to the microcontroller and a simple 
counting routine. And even if a CCC is used, 

I’ve not seen an appliance which makes use 
of a date function — so why would the date 
stop it operating? 

And even on a PC, the hysteria has gone 
too far. I’m sure many people believe their 
old PC will stop when 2000 starts. Again, 
why would it? The CCC doesn 7 control the 
PC; DOS does. At boot-up, DOS reads the 
CCC time and date (with the year stored as 
two digits in old machines), and from then 
on maintains (updates) the time using its 
own crystal oscillator (CPU clock). So if 
DOS interprets the year 2000 as 1900 (or 
more likely as 1980), so what? DOS doesn 7 
care what the date is. 

Of course DOS’s interpretation of the day of 
the week will be wrong, but that still won 7 
cause the PC to crash. Apart from time/date 
stamping files saved to disk, DOS simply stores 
(and updates) the time/date information, and 
passes it on to programs that ask for it. 

And that’s where problems begin. If you 
can live with the fact that files stored on your 
disk will look as though they were stored 
before personal computers were widespread, 
and if you don 7 mind editing the day/dates 
automatically inserted by your wordproces- 
sor (or other application), you can still con¬ 
tinue to use the majority of your programs. 

But problems will occur in programs 
which use the date for comparisons. 
Examples are accounting programs, which 
‘age ’ debts, and automatic backup programs 

ELECTRONICS Australia, September 1998 67 

which make backup decisions based on the 
date of disk files compared with the current 
(system) date. Programs such as these will 
probably not work properly, but these are 
minority uses for most home users. 

Sure, big institutions and companies with 
financial and accounting software systems 
will need to do something, and small busi¬ 
ness and home PC users will need to make a 
few checks (or test beforehand — see the BSI 
site below). So please, hose down the para¬ 
noia regarding domestic appliances, before 
my sides split! 

By the way, for a technical discussion on 
the Y2K problem, visit the British Standards 
Institute (BSI) site: 
bsi/disc/year2000.html. (Daniel Ford, BE, 
MBA, SMIREE, Managing Director, 
Advanced Solutions P/L, Beecroft, NSW) 

Thanks for this information Daniel, and 
for the website address. As you and Geoff 
say, date-dependent microcontrollers are 
somewhat in the minority. And again it 
depends on the code written for the device, 
not the actual micro. 

So that’s a look at home appliances with a 
microcontroller. The message seems to be 
‘don’t worry’, at least as far as our two cor¬ 
respondents are concerned. Now let’s see 
what the BSI website has to say. 

BSI’s Y2K website 

Clearly the BSI is taking the problem seri¬ 
ously. There’s a wealth of information on 
their site, including documents you can 
download. I looked at two different pages, 

and the following is an edited extract from a 
much longer discussion of the problem: 

Only when an organisation has analysed 
the Y2K problem and its business risks can it 
have an accurate picture of the scale of the 
task and the time and resources needed to fix 
it. Unfortunately, such a picture is typically 
more difficult, more expensive and more 
draining on resources than any of their esti¬ 
mates. Or as Caroline Bramley put it; “The 
Year 2000 problem is like an onion. The 
more layers you peel, the more you find. The 
more you find, the more you cry. ” 

This is a topic we could explore a lot 
more, but I think we’ve got the message. If 
you own a company that relies on computer 
systems, be it on your own head if you don’t 
ensure the system is 2000 compliant. For the 
rest of us, check the VCR for compliance. 

Lithium rechargeables 

In the June issue, a reader (E. De Longis, 
Midvale, WA) asked about charging 
Panasonic VL2330 vanadium pentoxide 
lithium rechargeable batteries. In answer to 
the question, Daniel Ford (see above) has 
suggested the following: 

I don’t know how to charge these batter¬ 
ies, having only used Sanyo Mn02Li 
rechargeables, but I suggest your correspon¬ 
dent contacts Premier Batteries, phone (02) 
9755 1845. This company seems to know 
almost everything about almost every type of 
battery in common use. 

Thanks again, Daniel. These days it’s 
almost impossible to keep track of the many 

types of rechargeable batteries. However, 
charging them is one thing — what about 
storing them? 

Storing NiCads 

The following question is one I’m sure a lot 
of readers might have wondered about... 

My laptop computer is powered by a 
NiCad battery pack. However as I don't use 
the laptop all that often (only on trips), and 
bearing in mind the NiCad ‘memory effect’, 
I wonder what I should do about the battery 
pack. Should I regularly recharge it to keep 
it in its best condition, or is it OK to leave it 
discharged for say six months at a time? The 
packs seem to be fully discharged when you 
buy them. (Andrew Palmer, Leura NSW) 

Sealed NiCads can be stored indefinitely 
in a discharged state, or in any state of 
charge without significant loss of life. 
Ideally they should be stored in a clean, dry 
environment below 50°C. There’s no need to 
regularly charge them, although if they are 
left standing for a long time, you might need 
to charge-discharge them several times to 
regain their capacity. In this case, the first 
charge should be for a 24-hour period 
(instead of the usual 14), at the CIO rate 
(charge current one-tenth the ampere hour 
capacity of the battery). 

The only other maintenance is to remove 
any crystalline growth from around the seal¬ 
ing. This growth is not detrimental to the 
battery, and can be prevented by smearing 
the area with silicone grease. 

Now for more on the ampere hour capaci¬ 
ty of a battery pack. 

Tiny tube battery 

The next letter takes me to task about my 
description of the battery pack in the ‘Tiny 
Tube portable lights’ described in the April 
and May 1998 issues. 

In the tiny tube light articles, you say each 
NiCad cell in the battery pack has a capaci¬ 
ty of 63mAh. You also say in the article "we 
made up a pack from 30 of these cells to give 
three 12V batteries in parallel, with a total 
capacity of around 1.9Ah. ’’ 

If 30 cells are connected in parallel, you 
get a battery with a 1.9Ah capacity, but with 
a terminal voltage of 1.2 V. If 10 of these cells 
are connected in series, you get a 12V bat¬ 
tery, but with a capacity of 63mAh. 
Connecting three of these in parallel gives a 
capacity of 190mAh, not the 1.9Ah you claim. 

There’s further inconsistency when you 
say the 14-hour charge current to each 


ELECTRONICS Australia, September 1998 

series pack is 40mA, as this implies a capac¬ 
ity (for 10 cells in series) of600mAh. I would 
believe this if the cells were rated at 
63OmAh. Incidentally, the volume of these 
cells is around that of a 600mAh AA size 
NiCad. What is the reality of the situation? 
(Ian Darby, email) 

Fair questions, Ian. First let’s look at 
what’s meant by an ampere-hour rating. 
Although it suggests a current rating, it is in 
fact an energy or capacity rating. For exam¬ 
ple, a 63mAh NiCad can deliver 6.3mA for 
10 hours, or ignoring other effects, 63mA for 
one hour, or 630mA for one tenth of an hour. 
The current capability of a cell is 
determined by its internal resis¬ 
tance, which in turn depends on its 

When cells are connected in series 
or in parallel, the total stored energy 
is the sum of the stored energy in 
each cell. Now you might think that 
when cells are in series, because the 
same current is flowing through 
each cell, the chemical action to cre¬ 
ate the current is the same in each 
cell. Not so. If you connect say ten 
2V cells in series, with each cell 
rated at 1 Ah, you get a lOAh battery 
with a terminal voltage of 20V. If 
the battery is connected across a 20- 
ohm resistor, a current of 1A flows. 
However, compared to a single cell, 
there’s now 10 times the quantity of 
chemicals to produce the current. 
Therefore a current of 1A will flow 
for 10 hours. 

Now to your question about charging the 
cells. When 10 by 63mAh cells are in series, 
the total capacity is 630mAh. The charge cur¬ 
rent at the CIO rate (or 14 hour rate) is there¬ 
fore 63mA, which is what the circuit does 
(more or less). The CIO discharge (10-hour 
discharge time) is also 63mA. Notice there’s 
more energy put into the battery than taken 
from it, due to the efficiency of the NiCads. 

As for the size of the cells, I have to agree 
that their physical size suggests a higher 
ampere hour rating. However, they come 
from a pack of six cells (in series), with the 
pack rated by the manufacturer at 380mAh. 
Hence the 63mAh rating for each cell. My 
guess is the manufacturer is being very con¬ 
servative about the rating. And while we’re 
talking about the tiny tube lights: 

Coax voltage rating 

This letter questions the use of the coax 
cable used in the prototype to connect the 
tiny tube in the strobe-beacon light described 
in the May issue. 

Thanks for a great project. May I suggest 
however that twin coax from a set of head¬ 
phones is hardly a safe cable for a high volt¬ 

age circuit. The circuit is labelled Caution - 
High Voltage, so why use a cable designed 
for a low voltage circuit. You wouldn’t 
dream of using this cable in a 240V circuit, 
no matter how light the load. Maybe a cau¬ 
tionary note should be published. (A.J. 
Lowe, Bardon, Qld) 

Yes, I admit it seems an odd choice of 
cable. The peak voltage across the tube is 
around 380V, much the same as the peak 
voltage from a 240V AC source. However 
the important difference between a 240V 
power outlet and the output of the tiny tube 
inverter is the current capability. The cable 

Fig. 1 


(Vpk = 400V) 

Fig.1: Suggested setup for testing a 275V 

used in the prototype is thin twin coax, with 
each cable individually insulated with a rub¬ 
ber coating. The earth braid surrounding 
each cable is not used. 

This means there’s at least 0.5mm of rubber 
insulation between each cable. The dielectric 
strength of rubber is somewhere between 10 
and 20 times higher than air, or around 
30kV/mm. This means, at a conservative esti¬ 
mate, at least 15kV is needed between the 
cables to cause the insulation to break down. 

Being a construction project, we assume 
readers will choose cables to suit the appli¬ 
cation of a project. If you intend using the 
tiny tube light in situations where the cable 
could be subjected to physical abuse or 
strain, then clearly you should use cable with 
heavier insulation. In normal use, this is not 
a problem. However, thank you Mr Lowe, 
for raising the point. Yes, as with any high 
voltage circuit, caution is essential! 

MOV rating 

A MOV or metal oxide varistor is often 
called a voltage suppressor. Although 

they’re used extensively, cost less than $2 
and are readily available, they are still an 
obscure device to many people. This letter 
asks questions about MO Vs that others 
might have wondered about: 

I use MOVs to suppress the back EMF 
across a relay coil. I also use them between 
phase and neutral to protect equipment from 
voltage transients. MOVs are generally given 
a rating in joules, which I believe means the 
device has a limited life based on this rating. 
How can I test a MOV without using an over¬ 
voltage source and a CRO? Commercial 
surge protectors often have an in-built alarm 
to indicate the device needs replac¬ 
ing, but I suspect this is simply a 
fuse-type indicator. (Kim Pederson, 
Port Moresby, PNG) 

A typical mains-rated MOV has a 
voltage rating of 275V, and an ener¬ 
gy rating of between 20 and 40J. 
One joule per second is a power of 
one watt, so a 40J device can handle 
40W of power for one second. 
Extrapolating backwards, the same 
device can handle 400W for 0.1s, 
and 4kW for 10ms, which is the 
duration of half a cycle of mains 
power. That is, the allowable fault 
current for 10ms is around 14A, usu¬ 
ally enough to blow a fuse. 

Unfortunately, testing a MOV 
takes longer than a few seconds, 
which means using a test current of a 
few milliamps. A test method I’ve 
used is shown in Fig.l. If the MOV 
is working, the AC voltmeter will 
indicate a voltage proportional to the current 
flowing in the resistor. Naturally you should 
First make sure the MOV is not a short-cir¬ 
cuit. I don’t know of any test method that 
doesn’t involve a suitable voltage source. 


This month’s question comes from Jim 
Lawler, of Geilston Bay in Tasmania. The 
answer to the question can be calculated, but 
even trying to guess it should prove interest¬ 
ing. It’s about the range of length measure¬ 
ments we need to perform. 

Consider the smallest distance and the 
largest distance man needs to measure. What 
is the difference in centimetres (expressed as 
a power of 10) between the two? 

Answer to August’s What 

The answer for circuit (a) is 300Q, which is 
obvious as the resistors are in series. Circuit 
(b) also poses little difficulty, as the jumper 
shorts out two resistors, leaving a total resis¬ 
tance of 100£L Circuit (c) has a resistance of 
33.333Q, as although not obvious, the three 
resistors are in parallel. It often helps to 
redraw the circuit! ❖ 

ELECTRONICS Australia, September 1998 


Vintage Radio 

Two Valve Sets — 1927 to the pre octal era 

1927 can be regarded as the year that all-electric sets were 
introduced. As the rectifier was at first not counted as a 
‘valve’, a 2/3-valve electric set was considered as a two-valver. 
So from 1927 on, there’s plenty to talk about when it comes to 

‘two valve’ receivers... 

T here are no definitive dates for the intro¬ 
duction of new ideas etc. Rather a date is 
claimed that is generally acknowledged 
to be when the new ideas began to penetrate 
the market. So, for 1927, 1928 and perhaps 
1929 and 1930 as well, there were still many 
battery operated two-triode transformer cou¬ 
pled radios being built by enthusiasts. 

The electric sets began to make their 
presence in about 1927. In the early years 
they were all-triode affairs, comprising usu¬ 
ally around six stages plus a rectifier. When 
used with the then-new balanced amature 
or cone speakers, they can to this day give 
a reasonable acount of themselves. 

Did we have battery powered all triode 
two-valvers capable of loudspeaker opera¬ 
tion? There was one particular English 
radio, made by Kolster-Brandes Ltd and 
marketed in conjunction with cigarette 
manufacturer Godfrey Phillips. Evidently, 

if you collected 500 vouchers from the 10- 
packs of ‘BDV’ cigarettes, you got the 
radio for free! Given that in 1930 there 
were supposedly no ills associated with cig¬ 
arette smoking, for the sum of £12/10/- you 
got to smoke your 5000 durries and got a 
free wireless. Not a bad deal, really! 

This dinkie little set is illustrated in Fig.l. 
It is fully enclosed in a bakelite case, a 7-1/4” 
cube, uses rather surprisingly French ‘Fotos’ 
triodes, and requires external batteries. 

In this country, the ‘Crosley’ model 51, a 
two-valver, was being offered for as little as 
£5/10/- complete, and was said to work a 
loudspeaker. An advert is shown in Fig.2. It 
must be stressed that by 1928 or so, many 
of the stations had increased their transmis¬ 
sion power to up to 5000 watts in some 
cases, with many being in the 1000-2000W 
range. Compared with the 300 - 500W lev¬ 
els of two or three years earlier, the increase 

Fig.l: The English made Kolster-Brandes 
two-valver of 1930 came free with 500 
cigarette coupons, in an offer from the 
Godfrey Phillips tobacco company. 

in transmitted power no doubt contributed 
to the ability of little sets such as the 
Crosley 51 to drive a loudspeaker. 

One of the locally made all triode two- 
valvers was the ‘Astor’ Electric Two of 
1930, and Stromberg Carlson also released 
an all-triode electric model in a most pre¬ 
tentious cabinet, with an equally preten¬ 
tious ‘quarter-acre’ chassis. 

The Philips 2516 

The Philips 2516 came pretty close to a two- 
triode loudspeaker radio. It is a triode regen¬ 
erative detector, transformer coupled to an 
output stage using the new ‘penthode’ (as 
they were first called). When used with a 
long wire antenna and a sensitive Philips 
speaker, loudspeaker results were indeed 
possible. It must be stated that the Philips 
‘Sevenette’ and ‘PCJJ’ speakers were very 
good for their times, and sound quite accept¬ 
able even today. 

Fig. 3: Inside the Philips 2516, an all-electric ‘two valver '. 
Outside, it looked very similar to their well-known battery 
eliminators of the day — deceiving many would-be collectors. 

70 ELECTRONICS Australia, September 1998 

by Roger Johnson 

The inside of a Philips 2516 is illustrated 
in Fig.3. The circuit holds no surprises, and 
consists of an E415 or similar triode, a 
B443 output and a 506 rectifier, all with 
European bases. 

Unfortunately, this set has all the hall¬ 
marks of ‘Philip’s fillips’ and is con¬ 
structed in the three dimensional mode. 
There is a four-position antenna connec¬ 
tion comprising a link with a moulded 
bakelite handle, and two rows 
of four sockets. Position one 
uses the dubious practice of 
using the mains cord as an 
antenna, in that the mains is 
connected to the antenna termi¬ 
nal of the coil via a mica capac¬ 
itor of about 500pF. In the other 
three settings, an external anten¬ 
na is connected by one of the 
three small value capacitors to 
the coil. A two-position switch 
selects a tuning range of either 
2000-800kHz or 1100-430kHz. 

Between the tuned circuit and 
the grid capacitor is what can 
only be described as a grid stop¬ 
per of 350 ohms. Just what pur¬ 
pose it serves is debatable. 

(Surely it couldn’t be there to 
prevent parasitic oscillations?) 

At the rear of the set are two 
sockets marked ‘G’. These are 
obviously for gramophone input. 

One connection is direct to the 

radios, these sets were known to be con¬ 
fused with the Philips ‘B’ and ‘C’ battery 
eliminators, and as a result were often over¬ 
looked at auction sales. Prudent collectors 
recognised them immediately, and because 
of the lack of interest, purchased them very 
cheaply indeed! 

For all the unusual layout and wiring 
practices, the 2516 is beautifully made, is 
well designed, and is a good performer. 

‘Screen grid’ valves 

By about 1928 the new tetrode type UY224 
was released, and made its way to this coun¬ 
try by about 1929, appearing in the contem- 
pory magazines first by way of introduction 
and then in illustrative circuits. A similar 
story applies to the Philips E442, and the bat¬ 
tery types that first appeared such as the 
American UX222 (which has a 3.3V fila¬ 
ment, incidentally), the Marconi 
S625 and Philips A442, and a 
host of other British types. 
Together with the newer output 
pentodes B443, C443, and type 
247, a higher gain receiver was 
now possible. 

The screen grid valves were 
unsuitable for transformer cou¬ 
pling. This is a characteristic of 
high impedance valves, be they 
high gain triodes or pentodes. 

Particularly when using the 
UY224, the standard proce¬ 
dure was to use ‘impedance 
coupling’ (otherwise known 
as choke coupling), from the 
224 to the output stage. 
Basically, the anode load 
resistance of usually 250k 
was replaced by an an iron x 
cored choke of about 10 hen- 
rys (or greater) and having a 
DC resistance of perhaps only 
3k or so. 

CROSLEY” 2-valve Radio 

A splendid double circuit receiver, extremely 
selective, it works all local stations at speaker 

The “Crosley” compares more than 
favorably with sets twice the price. £ PJ* / ^ f 
Complete with valves, batteries, 3L O / X II / 
aerial and phones. f ' 


grid, and the other is a point on 
the negative supply line at -4.7V. The com¬ 
bined decoupling resistor, grid leak and 
voltage dividing resistors present an input 
impedance of 2.2 megohms, across which 
is a bias of -4.2V. When connected to a 
comparatively low DC resistance magnetic 
pick-up, this bias will now appear at the 
grid of the E415, which represents about 
the right voltage for the anode potential of 
70 volts for maximum class A operation. A 
very clever piece of circuitry... 

The detector is of the ‘leaky grid’ type, 
and reaction is controlled by a vario-cou- 
pler. As far as the rest of the circuit is con¬ 
cerned, it is conventional. HT filtering is in 
the negative line via a two-section choke. 
There is decoupling just about everywhere 
because of the low value filter capacitors 
all paper types, of only luF. There is no 
volume control. 

The cabinet of this set looks rather famil¬ 
iar. In the early days of collecting vintage 

Fig.2: The Crosley model 51, a battery 
two-valver advertised in The Listener In 
for 15 Feb 1928. As you can see from the 
circuit below it was very basic. 



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Tel/Fax (03) 9571 1160 Mobile 0411 856 171 
Email: evatco © 

ELECTRONICS Australia, September 1998 



Vintage Radio 


ClL * 

A ^WjM. 

D 5? P247 /?/, /QOOOsi (S&ecfmry) 

R 2 t MC(jn- . /?3, 150,000jt. foqocc -n.. 

lOqoooj*-. CiA t ’inf C^Z 'O/nf 
C*d. OOOInf C$ 000//*}-. C 5 ,b fnft/ec/’ro/yFc, 
Sp ea I er //eld z too si fyp ed&t zoo s^ 


noDfL 22 

Fig.4: Very typical of the early 1930s two-valve electric sets is the Healing model 22 
circuit shown here. Regenerative detector D drives output stage P directly. 

This was done to overcome the problems 
of transformer coupling, yet still maintain a 
substantial anode potential by virtue of the 
reduced DC voltage drop across the wind¬ 
ing. The impedance of the choke at audio 
frequencies, which represents the true plate 
load, is up around 100k ohms. The old ‘24A 
simply lost too much gain with the reduced 
anode voltage caused by a conventional 
resistor as the plate load... 

With the later series of 57/2A5 or 6C6/42 
combinations the problem was not so bad, 
and the standard form of R-C coupling was 
the norm. 

Commercial regen sets 

There are absolutely no shortage of commer¬ 
cial two-valve electric sets based on a regen¬ 
erative detector, either in the literature or 
amongst collectors. Many manufacturers 
offered them. ‘Eclipse’ chassis in particular 
were offered under different labels for the 
various department stores’ own brand budget 
priced sets. For most sets the valve combina¬ 
tions were a 224A driving a 47, or various 
Philips types such as E452 and E443H, fol¬ 
lowed by the later combinations of 57/2A5 
and 6C6/42. 

Properly designed, these sets could per¬ 
form quite well. However, there was little 
point in offering a set for half the cost of a 
superhet that performed better than half as 
well as a superhet, now was there? Some of 
the tricks used by the manufacturers were 
reduced screen voltage on the detector 
stage, thereby reducing the stage gain, and 
over bias on the output stage. In this stage 
this had two effects; it limited the plate cur¬ 
rent and hence the power delivered to the 
speaker, and it reduced the sensitivity! 

The coils for these sets were invariably of 
the solenoid type, wound on either an 
impregnated cardboard or bakclite former 
and using solid enamelled wire of about 32 
SWG. Some of the very early sets used cot¬ 
ton covered wire. The antenna connection 
was either via a tap towards the earthy end 
of the coil, or a small coil wound on a bob¬ 
bin placed inside the coil former. The aeri¬ 
al coil primary invariably had one or more 
taps. The antenna also tended to be gener¬ 
ously coupled to the tuning circuit, making 
station separation of close stations very dif¬ 
ficult — hence the choice of antenna con¬ 
nection. In fairness, though, in the early 
1930s there simply weren’t as many sta¬ 
tions as there are today, and they were a lit¬ 
tle further apart. 

Here in Adelaide, the test of a good sin- 
gle-tuned-circuit regenerative detector is 
to separate 5DN on 1323kHz and 5AA on 

1397kHz. Not many of them pass the test. 
The only way to achieve it is to reduce 
the antenna coupling. However, many 
circuits had the volume control, which 
was a 1000 or 2500 ohm pot, simply 
shunted directly across the primary wind¬ 
ing, with the wiper connected to earth. 
Removing turns from the primary then 
made the volume control more difficult 
and it also tended to dampen the tuned 
circuit — making tuning more difficult. 

In cases like this, the antenna coupling 
can be reduced by experimenting with a 
small value fixed capacitor in series with the 
antenna and the antenna winding of the coil. 
However performance at the low frequency 
end of the coil drops off appreciably... 

Reducing the antenna coupling also 
reduces the gain. One sure way to improve 
the gain is to operate the detector screen at 
maximum value. This means modifying the 
circuit by substituting a screen dropping 
resistor with one that is different to the orig¬ 
inal value. Such modifications are the sub¬ 
ject of vigorous debate between the purists 
and the pragmatists. One neat conscience¬ 
saving ploy is to make the receiver work in 
a practical manner, whilst kidding oneself 
that one ‘can always change it back to orig¬ 
inal if one chooses’. 

Shown in Fig.4 is the circuit for a 
Healing model 22 of 1932 vintage, which 
has most of the features described and nice¬ 
ly illustrates the piont. The screen voltage 

would be lower than maximum rating. 

When was the rectifier considered to be a 
‘valve’? After all, it’s only a dumb old twin 
diode; it doesn’t really Jo anything! 

Well, around the mid 1930s some slick 
fancy-pants salesman probably realised that 
since it was made of glass, you could plug 
it in, and it glowed in the dark like the oth¬ 
ers, then it was a valve. Suddenly, a ‘two 
valve’ set became a ‘three valve’ set, with 
all the added advantages a third valve 
offers. Ho hum.... 

Multiple valves 

In the pre-octal era came the type 53 and the 
later 6A6 valves. Although these were 
designed as a class B output valve, there 
were hobbyist circuits that used them as a tri- 
ode regenerative detector with an R-C cou¬ 
pled audio and thence to a pentode output. 
Good results were claimed. 

The other multiple valve of note was the 
6F7, which was originally intended as a 
mixer oscillator. This tube has separate 
pentode and triode units within the one 
envelope, sharing a common cathode. It 
was used for a variety of purposes other 
than its original intention. 

Because of the pentode section, the 6F7 
could be used as a RF amplifier and regen¬ 
erative detector triode, and then R-C cou¬ 
pled to an output stage. Again, good results 
were claimed, because of the increased 
selectivity. ❖ 

ELECTRONICS Australia, September 1998 


‘Front End’ for PC 
Audio Recording 

(Continued from page 49) 

a template for drilling it too. Here the four 
3mm holes only need de-burring. You might 
also want to solder the end of a short length 
of hookup wire to the copper laminate, for 
convenient connection to the PCB earth 
when they’re in situ. 

It should now be possible to mount the 
PCB assembly inside the case bottom. I used 
12mm-long 3mm countersink head screws, 
passing through the case bottom and then 
through the shield plate before star lock- 
washers and nuts were fitted (mainly to act as 
short spacers for the PCB). Then, after 
checking that all of the component leads 
were trimmed short under the PCB, to pre¬ 
vent shorts, the PCB was fitted to the remain¬ 
ing screw ends and a further lockwasher and 
nut added to each screw to fasten it in place. 

After mounting all of the controls to the 
front panel and the connectors to the rear 
panel, you’re then ready for the final stage: 
adding all of the off-board wiring, between 
the PCB and the controls and connectors. 
This is fairly straightforward, but take it 
easily and carefully to avoid errors. 

Note that shielded audio cable should be 
used for the wiring to the microphone jack 

and magnetic pickup input sockets, at the 
very least. You may also want to use this 
cable for the wiring to the Tape/Line input 
sockets, and perhaps that to SW1, RV1 and 
RV2 as well — to minimise susceptibility to 
noise and hum, etc. It’s probably not neces¬ 
sary to shield the wiring to SW2, RV3, RV4 
and the output connectors, though, as the sig¬ 
nal levels here are higher and the impedance 
levels lower. There’s also no need to shield 
the wiring to the power LED, of course. 

By the way, don’t forget to solder a lead to 
the metal bodies of each of the pots on the front 
panel, with its ‘other end’ connected to signal 
earth — say via the earth lead from the LED. 
This should ensure good earthing of the con¬ 
trol cases and front panel, and allow them to 
act as a shield plate above the PCB assembly. 

With this final wiring done, your 
Recording Front End should be just about 
complete. As there’s no actual setting-up 
required, little should remain except assem¬ 
bly of the case, and connecting it up to your 
PC for a trial run. 

By the way, I’ve discovered (largely the 
hard way) that there are a few tricks to get¬ 
ting the best results when you’re using the 
RFE with a PC and sound card for making 
digital audio recordings and transcriptions. 
In a follow-up article, I’ll try to pass on 
some some suggestions and helpful tips on 
putting it to use. ❖ 

Subscribe to 
Electronics Australia 
and save $$$$ 

See page 82 for details. 

Valve Electronics 

Pty Ltd ACN 001944369 

Overhaul custom work & 
restoration: all types of valve 
amplifiers radios & equipment. 
New, NOS & S/H parts for 
sale. Catalogue on request. 

P/0 Box 467 Newtown NSW 2042 
Ph 02 9557 2212 Car 019449311 
Fax 02 9516 3981 

ELECTRONICS Australia, September 1998 



Computer Clinic 

Creating your own Windows program with the CGI... 

L ast month, after answering Mr Healy’s 
query about Windows programming, it 
struck me that there is a way to create a 
Windows program without having to shell 
out for an expensive, often hard to drive, 
programming language. There is a way to 
use your own favourite DOS language, be it 
Pascal, C, a batch file, or (for the strong of 
stomach) BASIC to create a perfectly good 
Win95-looking app without ever having to 
deal with the mind-numbing ugliness of 
Windows system calls. What’s more, you 
get to use an interface that’s probably more 
widely used than any other application: the 
web browser! That’s right, this month I’m 
taking you on a lightning tour through the 
weird world of the CGI. 

Before I go any further. I’d just like to 
point out that this isn’t the most eminently 
practical approach to things (or very easy to 
distribute), as the setup is somewhat fragile 
and takes a fair amount of overhead to sup¬ 
port it. Also, the only controls you can use 
are radio buttons, check boxes, text boxes 
and drop-down lists. No menus, no message 
boxes and no multiple windows. It is fun to 
work with, however, and you will learn a lot 
about what goes on whenever you use a 
search engine, see a hit counter or look 
through a webcam. 

Are you being served? 

Apart from a web browser, all you need is an 
HTTP server. HTTP servers (also known as 
web servers) are the programs that make the 
World Wide Web possible. They pick up 
HTTP requests from the network and send 

the appropriate web page back to the com¬ 
puter requesting it. As well as simply send¬ 
ing HTML files and pictures, they have 
another major function that has made the 
web what it is today: the Common Gateway 
Interface (CGI). 

The CGI is a mechanism that allows the 
server to run an external program, and send 
that program’s output back to the user as a 
web page. This is how search engines work. 
You type your query into a form on the main 
page, and the web server takes the form and 
hands it to the search software, which spits 
back the results of your query, nicely for¬ 
matted in HTML. The web server then sends 
this output back to you, making it look as 
though it already had a whole web page 
devoted to your query just sitting there. 

There are lots of cheap or free HTTP 
server programs out there. The one I use is 
OmniHTTP vl.01, available from 
html. It’s small, it works, and it’s free. 
Once you run the install program, every¬ 
thing is ready to go; just point your brows¬ 
er at http://l, and you should see an 
FTP-style directory listing. Click on 
Default.htm, and you should see the intro¬ 
duction page. 

There is one minor inconvenience with 
Microsoft Internet Explorer 4: If you are 
working offline and try to access the local 
server, IE4 will quite unnecessarily try to 
connect you to your ISP. If this happens, 
cancel the ‘Connect to:’ requester, go to the 
File menu, deselect ‘Work Offline’, and try 
again. Netscape users don’t get this problem; 
but then again, they have to use Netscape, 
which is almost as annoying. 

Local hero 

If you’re thinking T can’t do this. I’m not on 
the net’, then fear not. You don’t need a web 
site, a connection to the internet, a network 
card or even a modem. The clever people 
who designed TCP/IP (the network protocol 
used on the internet) reserved the IP address as a loopback address. This means, 
in effect, that data requests sent to 
don’t go through the network card or modem, 
but go straight to your HTTP server instead. 

If you have no connection to the internet at 
all, then you will need to make sure that 
TCP/IP is installed on your computer. To 
check whether you have it, go to Control 
panel|Network, and look at the list that 
appears. If you don’t see TCP/IP anywhere, 
click Add, Protocol, Microsoft, TCP/IP, Ok. 
You’ll be prompted to insert your Win95 
CD, and to restart your computer. 

How to do it 

The actual implementation of CGI program¬ 
ming is very simple. You will need to make 
an HTML page, using one of the many 
HTML editors out there such as HoTMetaL 
or Microsoft FrontPage. (If you are feeling 
adventurous, stick with good old Notepad. 
You get a lot more control over the finished 
result, and a lot more kudos as well.) 

The web page should contain a hypertext 
link to your CGI program, either in the form 
of a standard <A HREF> link or a form. All 
you do is put your program into the CGI- 
BIN subdirectory of your web server’s direc- 


<BODY BACKGROUND="http : // . gif"> pj a 1 


<Hl>Demo form</Hl> 




<TDXH3>First name : </h3><SELECT NAME="FirstName"> 




<TDXH3>Last name : </H3><INPUT NAME="LastName" TYPE=TEXTX/TD> 

<TD ALIGN=RIGHTXH3>Pet owned :</H3> 










ELECTRONICS Australia, September 1998 

by Jean-Baptiste Cattley 

@echo off 

printf "Content-type: text/html" 


printf "" 

printf "<HTMLXHEAD><TITLE>CGI slideshow batch file demo</TITLEx/HEAD>" 

printf "<BODY BGCOLOR=*#F0F080'>" 

printf "<CENTER><Hl>Images in c:\win95</HlXHR>" 

for i%s in (c:\win95\* .bmp) do printf "%%s:<BRXIMG SRC= * %%s ' XBRXBR>" 

tory, and provide a link to it in your web 
page. Clicking the link will execute the pro¬ 
gram, which will in turn produce a new page 
that will display on your browser. 

If the program is self-contained (i.e. it 
doesn’t require any input from the user), 
you can simply link to the program as 
though it were another web page, for 
example: <A HREF-’ 
bin/mycgi.exe”> Run the CGI app! </A>. 
The program simply prints the informa¬ 
tion to its standard output, using printf(), 
PRINT, or however your favourite lan¬ 
guage normally produces text. 

If your program needs information 
from the user, things get a little more 
complicated. You need to send the infor¬ 
mation to the program using the HTML 
<FORM> element (used to create check 
boxes, text areas, etc). The <FORM> ele¬ 
ment has two major attributes: ACTION, 
containing the link to the CGI program 
(as above), and METHOD, which con¬ 
trols how the information is to be sent. I’ll 
be using METHOD=GET in this article, 
which puts the contents of the form into the 
QUERY STRING environment variable. 
(The other option is METHOD=POST, 
which makes the form data available on the 
program’s standard input. More flexible, but 
not as simple.) 

A complete HTML form, then, might look 
something like Fig.l. The INPUT sub-ele¬ 
ments are used to create the actual controls on 
the form. The TYPE and VALUE attributes 
define the controls’ appearance, but what 
we’re interested in the moment is the NAME 
attribute. When the form is submitted, the 
form data is encoded in name=value pairs 
separated by ampersands, so the form in Fig.l 
would produce FirstName=Fred&Last 
Name=Bloggins&Pet=Chicken. This string 
can then be read by your program (using 
getenv() or equivalent) and the information 

CGI in action 

Once your program has digested the data, it 
needs to return the program’s output to the 
browser in HTML format. First, though, it 
must tell the web server that it is sending a 

web page. This is done by outputting 
“Content-type: text/html” and one blank line 
before sending the rest of the page. 

That accomplished, all it has to do is to 
dress the output up in HTML format. This can 


E*» E<* lio 

O O (2 

S3 & 

TioTxl l 



OArg a w ti v cg «•** 

Using the CGI for trivial purposes 

Fig.2: A very simple CGI-based program in 
action. It does simple maths with two 
selected numbers. 

Fig.3 shows another little demo that 1 
knocked together; this one produces a simple 
slide show of all files in a given directory. This 
wouldn’t be terribly interesting if it weren’t for 
the fact that it was produced with an ordinary 
DOS batch file. This would have been a 
more or less trivial task, except that DOS’ 
ECHO command can’t handle the angle 
brackets used in HTML, and tries to treat 
them as redirection characters. Putting the 
string to be printed in quotes solves the 
redirection problem, but causes the quota¬ 
tion marks to be printed as well, dotting 
redundant punctuation all over the page... 

To get around this, I wrote a tiny C util¬ 
ity that does the job properly, and even 
expands environment variables. The only 
drawback is that you have to replace any 
quotation marks that you actually do 
want printed (around a link, for example) 
with backticks ('). Once again this utility 
is available online, as are all the programs 
I write for this column. 

Mind your language 

be as simple as sticking “<HTML><BODY>” 
on the front, and “</BODY></HTML>” on 
the end, but you can get as fancy as you like, 
with images, tables, more forms, or even 
frames if you want. 

You can see a decidedly non-fancy example 
in Fig.2. This little program, written in C, 
takes two numbers, and adds, subtracts, 
divides or multiplies them together, and dis¬ 
plays the result in graphical format. This is 
achieved by going through the result, digit by 
digit, and printing an HTML <IMG> tag for a 
GIF of that digit. (I created the images at about 
four in the morning, so please excuse the slop¬ 
py mousewriting.) It also prints its own calling 
form at the top of the page, so you can run it 
again without having to go back. 

The hardest part of writing the whole pro¬ 
gram was the string handling for extracting 
the numbers from the POST string. Once that 
was done, everything was plain sailing. The 
source is a little long to print here, but it’s 
available on the EA BBS and web site, along 
with the images and executable version. 

The upshot of all this, then, is that you can use 
virtually any language you like to write your 
program. It shouldn’t take very much work at 
all to adapt an existing program (assuming you 
have the source code, of course!) to the CGI. 
The only limitations are that program’s output 
must be redirectable to a file, and that it exits to 
DOS after completion. 

This does put a bit of a crimp in QBASIC, 
which uses direct screen output and returns 
to the editor after running the program. 
There are ways round this, however. If you 
you can just use PRINT #1 for outputting 
text, avoiding the direct-video text output. 
As for the retuming-to-editor problem, you 
can use one of the many shareware BASIC 
compilers out there to compile your program 
as an EXE that returns straight to DOS. 

For the C programmers among you, there 
are a number of CGI libraries out there that 
make CGI programming a lot nicer than the 
quick hack that I wrote. One such library is 
Eric E. Kim’s cgihtml package, available from\vare/cgihtml. ♦> 

ELECTRONICS Australia, September 1998 75 

Electronics Australia is one of the longest-run¬ 
ning technical magazines in the world. We started 
as Wireless Weekly \n August 1922 and became 
Radio and Hobbies in Australia in April 1939. The 
title was changed to Radio, Television and 
Hobbies in February 1955 and finally, to 
Electronics Australia in April 1965. Here’s some 
interesting items from past issues: 

SO years ago 

September 1948 

Waveforms made to Order: A new electronic circuit for med¬ 
ical diagnosis and research will produce any desired waveform 
when its shape is cut from cardboard and placed between a cath¬ 
ode ray tube and a photomultiplier tube. Wave characteristics 
become available which are difficult or impossible by means of 
ordinary electronic circuits. 

The device is designed to provide either single or repetitive 
stimuli, derived from a simple silhouette easily cut by following 
any desired curve drawn on cardboard. The mask so obtained is 
placed in contact with the screen of a CRT having a short-persis¬ 
tence phosphor, with the CRT trace spread vertically into a thin 
line by an RF oscillator. The line is caused to move from left to 
right by a relaxation oscillator, which sets the waveform fre¬ 
quency. An RCA 931-A or similar photomultiplier tube is placed 
about eight inches from the face of the CRT and mask. The 
amount of light which falls on the phototube is a function of the 
length of line which it sees at any instant, and this is determined 
by the shape of the mask. The output of the tube is approximate¬ 
ly 10 volts with a 750V power supply and a 50k£2 load resistor. 

2$ years ago 

September 1973 

Darwin-Mount Isa Link nears Completion: Spanning 1000 
miles of desert between Darwin and Mount Isa, Australia’s new 
$10 million microwave link is nearing completion. Consisting of 
43 repeater stations, some up to 250ft high, the new system will 
enable Darwin to dial direct to almost anywhere in Australia. 

The system will have an initial capacity of 1200 channels to 
provide telephone, telegraph and data communications facilities 
for a vast area of Australia’s north, and will link Darwin into the 
national subscriber trunk dialling network. 

Low cost Computer Graphics Terminal: A high performance 
minicomputer based graphics terminal priced from approximate¬ 
ly $10,000 has been announced by Digital Equipment Australia. 
The GT40 intelligent terminal links Digital’s PDP-11/10 mini¬ 
computer to a specially designed, hard-wired display processor 
and a 12-inch diagonal oscilloscope. A light pen, full ASCII key¬ 
board and character set, 31 special mathematical and scientific 
symbols, and an APO approved serial communications interface 
are standard features of the GT40. 

The low-cost terminal may be used either as a stand-alone 
graphics system or as a remote terminal interacting with various 
types of host computers. ♦> 



I Shape of an oscillation. (8) 

5 Rapid fluctuation of 

a picture. (6) 

10 Again inserts a cassette, 
cartridge etc. (7) 

II The initial phase. (7) 

12 Heavy metal. (4) 

13 Detect. (5) 

14 Brief signalling tones. (4) 

17 Winding machine. (5) 

18 Elementary gas. (6) 

21 Pertaining to certain iron 
compounds. (6) 

22 Desktop hardware item. (5) 

26 Built-in operating system. (4) 

27 Plural of vacuum. (5) 

28 Band instrument. (4) 

31 Valve. (7) 

32 State of non-transmission of 
radiated energy. (7) 

33 Co-inventor of the Geiger 
counter. (6) 

34 Inventor of the famous H4 

chronometer, John. 

(1693-1776). (8) 


1 Periodic variation of a 
sound’s pitch. (6) 

2 Name of effect where stress 
changes magnetism. (7) 

3 A character that signals 
some special condition. (4) 

4 A list for duty periods. (6) 

6 Radio engineers’ 
organisation. (1,1,1,1) 

7 Isotope of hydrogen. (7) 

8 Store for fixed amount 
of digital information. (8) 

9 Amplifying device. (7) 

15 Written piece of music. (5) 

16 Small power indicator: 
the .... light. (5) 

19 Popular brand of diskette. (8) 

20 Illegally copied for 
commercial use. (7) 

21 View facing forepart. (7) 

23 Acquires knowledge, 
systematically. (7) 

24 Visible atmospheric 
phenomenon. (6) 

25 Elementary particle. (6) 

29 Region of a magnet. (4) 

30 Organic filament. (4) ❖ 

August’s solution: 

HBHBmnnH hbbbiib 




ELECTRONICS Australia, September 1998 


Picture courtesy Apple Computer Inc., Gary Parker 

Electronics Australia's 



Intel announces Pentium II 
'Xeon' processor for 
servers & workstations 

Texas Instruments sells its 
DRAM business tn Micrnn 

Designer's guide tn charging 

Li-Ion Batteries: 

: . 



Semiconductor distributor Fastron Technologies has moved to these 
impressive new premises at 25 Kingsley Close , Rowville 3178; phone 
(03) 9763 5155. 

Compaq closing Digital 
assy plant in Sydney 

Motorola to mass 
produce new ‘biochips’ 

Rapid advances in medicine, health care and 
agriculture are expected from a joint- 
research project announced by Motorola, 
Packard Instrument Company and the US 
Department of Energy’s Argonne National 
Laboratory. The project, which aims at com¬ 
mercializing and marketing advanced 
biochips and related analytical technologies, 
is expected to make the process of decoding 
genes, human or otherwise, 1000 times 
faster than with current technologies. 

Motorola will develop manufacturing 
processes to mass produce the biochips, and 
Packard will develop and manufacture the 
analytical instruments to process and ana¬ 
lyze them. Argonne’s contribution, in con¬ 
junction with its Moscow research partner 
the Russian Academy of Science’s 
Engelhardt Institute of Molecular Biology, is 
intellectual property in the form of 19 inven¬ 
tions related to biological microchips. 

Motorola and Packard will contribute a total 
of US$19 million over five years to support 
the joint-research agreement, making it one of 
the largest biotechnology joint-research agree¬ 
ments ever signed by a US Department of 
Energy laboratory. Argonne’s 19 inventions, 
which have been licensed exclusively to 
Motorola and Packard, are the result of more 
than $10 million in research support since 
1994 by the US Department of Energy, the 
Defense Advanced Research Projects Agency, 
the Russian Academy of Sciences, and the 
Russian Human Genome Program. 

Like computer chips, which perform millions 
of mathematical operations a second, biochips 
can perform thousands of biological reactions, 
such as decoding genes, in a few seconds. 

The Argonne/Engelhardt biochips employ 
a novel ‘micro-gel’ technology in which as 
many as 10,000 micro-structures are mount¬ 
ed on a single glass surface about the size of 
a microscopic slide. 

Each micro-gel is like a micro-test tube, in 
which chemical compounds can be tested 
against biological targets to provide answers 
to questions about DNA sequence, genetic 
variation, gene expression, protein interac¬ 
tion and immune response. 

In addition to being faster than conven¬ 
tional gene sequencing methods, these 
biochips provide a three-dimensional plat¬ 
form that allows greater sensitivity and accu¬ 
racy in assaying proteins, RNA and DNA. 

As part of the global rationalisation follow¬ 
ing the acquisition of Digital Equipment by 
Compaq Computer, Digital’s assembly plant 
in the Sydney suburb of Lane Cove is being 
closed. Its operations will be incorporated 
into Compaq’s existing configuration centre 
in Rydalmere, the company has announced. 

Compaq Australia’s MD Ian Penman, 
who will be running the combined operation 
in Australia, has announced that some 300- 
400 jobs will be lost in Australia as part of 
the merger. 

Voluntary recall of Tek’s 
TDS210& TDS220 

Tektronix is voluntarily recalling its model 
TDS210 and TDS220 oscilloscopes after 
determining that certain incorrect use of the 
product could cause the ground connection 
to fail. Although there have been reports of 
situations in which the ground lead on the 
oscilloscope has opened when the products 
were incorrectly used, the company is not 
aware of any injuries to users. However, a 
failure of the ground connection does have 
the potential of exposing the user to the risk 
of serious personal injury or death. 

If a user incorrectly connects a probe 
ground lead to a voltage source, or incorrect¬ 
ly touches the ground ring near the probe tip 
to a voltage source, a circuit board trace in 
the oscilloscope’s electrical ground path may 
open. Once this occurs, the product may 
appear to function normally; however, the 
unit is no longer properly grounded. 
Subsequent use of the product could then 
result in a serious electrical shock to the user. 

Tektronix is conducting the voluntary 

recall to prevent this possibility of injury to 
its customers and is part of the company’s 
overall commitment to providing reliable, 
safe and high-quality products. This recall 
applies to approximately 60,000 TDS210 
and TDS220 units with serial numbers 
below the following: 

TDS210: serial numbers below B049400 or 
CO 10880 

TDS220: serial numbers below B041060 or 

Customers should stop using the recalled 
oscilloscopes immediately and contact 
Tektronix to receive instructions on how to 
return the product for modification. 
Customers should not assume the product is 
properly grounded even if it appears to be 
functioning properly. 

Customers can receive instructions for 
returning the product by contacting Tektronix 
Australia at 1 800 023 342 ext. 193, at 800- 
835-9433 ext. 2400 in the US or by visiting 
the company’s web site at 

Alcatel plant 
sold to Bluegum 

Alcatel Australia’s manufacturing plant in 
Liverpool, NSW has been acquired by con¬ 
tract manufacturer Bluegum Technology, as 
part of a $250 million three-year agreement 
between the two companies for the outsourc¬ 
ing of Alcatel’s telephone, switches and net¬ 
work product manufacturing activities. The 
acquisition is said to position Bluegum 
among the top 30 private companies in 
Australia, and in the top 15 contract elec¬ 
tronics manufacturers in the world. 

Bluegum CEO Mr Paul Zuber said that 
the agreement would enable Australia to 


ELECTRONICS Australia, September 1998 

further develop its manufacturing potential 
at home. “The Australian electronics hard¬ 
ware manufacturing market is worth A$7-8 
billion, yet less than 15% is being serviced 
by contract manufacturers today”, com¬ 
mented Mr Zuber. 

Under the agreement, existing Alcatel 
operations and management will remain, 
providing a seamless transfer of current 
management and 400 employees to Bluegum 
on September 1. Peter Miller, manufacturing 
manager of the Alcatel Liverpool plant, 
becomes Director of Manufacturing for the 
new Bluegum Telecommunications. 

The agreement with Alcatel is a continua¬ 
tion of Bluegum’s expansion into the 
Australian electronics contract manufacturing 
business, which began with its purchase of 
IBM’s Wangaratta plant in November 1997. 

Iomega unveils 
new USB Zip drive 

Iomega Corporation has announced a new, 
external Zip drive for use with a Universal 
Serial Bus (USB) interface. The company 
demonstrated the new drive in conjunction 
with Apple Computer’s new iMac model in 
New York at the MacWorld exhibition in July. 
The new translucent ice-blue USB Zip drive 
will have the USB interface built into the 
drive, saving space on the desktop and elimi¬ 
nating the need for a larger parallel port or 
SCSI conversion cable. The USB Zip drive is 
designed to provide users of USB-equipped 
computers, with Mac OS 8.1 or Windows 98 
operating systems, the easy connectivity of a 
hot ‘plug and play’ solution. 

“IDC believes that USB will become prevalent 
in the market this year with an estimated 90% 
of desktops shipped this year with the technol¬ 
ogy”, said Kevin Hause, PC analyst 
with International Data 
Corporation. “USB’s market appeal 
is based on its plug and play func¬ 
tionality and ability to provide users 
with a single, higher bandwidth port 
for a range of peripherals.” 

USB is a low cost, high-speed 
peripheral expansion architec¬ 
ture that provides data transfer 
rates up to 12Mb/s. USB inter¬ 
facing peripherals can be 
plugged and unplugged from 
the USB interface anytime, 
without requiring the user to 
restart their system to initiate or 
re-initiate use. The USB spec 
also supports up to 127 devices 
on a single computer system. 

The new USB Zip drive is expected to be 
available late in 1998. The estimated US 
street price is not expected to exceed 
US$149. The drives will be designed to be 
compatible with an installed base of tens of 
millions of Mac and PC formatted Zip disks. 

Sanyo licenses PM’s 
HDCD technology 

Sanyo Electric’s MOS-LSI division, one of 
the world’s leading suppliers of integrated 
circuits for consumer audio CD playback 
systems, has licensed Pacific Microsonics’ 
high fidelity HDCD decoding and precision 
filtering technology for Sanyo’s new general 
market audio chip. 

“Sanyo is very pleased to be working with 
Pacific Microsonics because HDCD has 
become a symbol of high quality digital 
audio worldwide”, said Toshiyuki Ozawa, 
Department Manager of Sanyo’s System 
Development Division. “With Sanyo’s large 
scale integration design skills and high vol¬ 
ume manufacturing capability, we will be 
able to offer consumer electronics manufac¬ 
turers a high quality HDCD chip that meets 
both their performance and aggressive cost 

The new chip will be an enhanced ver¬ 
sion of Sanyo’s current industry leading 

general market audio product, which inte¬ 
grates all major CD player circuitry on a 
single chip. Sanyo will add the same high 
fidelity HDCD decoding and HDCD filter¬ 
ing technology used in Pacific 
Microsonics’ PMD-100 chip, a standard 
component in high end CD players around 

the world. Also, the D/A converters in the 
new chip will be upgraded from 16 to 18 
bits. Target consumer product applications 
include high volume CD players, changers, 
portables, mini-component systems and 
automotive audio products. Sanyo expects 
samples to be available in the second half 
of 1999, and production quantities to be 
available soon thereafter. 

In January, Motorola announced that it is 
adding HDCD to its 56362 DSP, and in 
March, Analog Devices announced it is 
adding HDCD to its SHARC DSP. Target 
consumer product applications for these chips 
include A/V receivers and DVD players. 

Developed by Pacific Microsonics in 
Berkeley, California, HDCD (High 
Definition Compatible Digital) is a patent¬ 
ed process for delivering on Compact Disc 
the full richness and detail of the original 
microphone feed. HDCD encoded CDs 
sound better because they are encoded with 
20 bits of real musical information as com¬ 
pared to 16 bits for conventional CDs. 

Philips shipping 
CleverCast DVB cards 

Philips Digital Video Systems Company, a 
leader in the field of digital data broadcasting, 
has begun mass production of the CleverCast 
PC-DVB Receiver card. Volume shipments 

Scientists and support 
people working in 
Antarctica can now 
use cellular phones to 
call anywhere in the 
world, thanks to a new 
cell site installed last 
May by Lucent 
engineers. The site is 
satellite-linked to 
Rivadavia in 

(Business Wire) 

HDCD provides more dynamic 
range, a focused 3-D sound stage 
and extremely natural musical 
timbre. HDCD recordings offer 
improved sound quality on any 
CD player, and when played on 
HDCD equipped players, they 
are claimed to provide the ulti¬ 
mate in sonic fidelity. 

Pacific Microsonics says that 
over 50 million HDCD CDs have 
been shipped to date and over 
100 HDCD equipped CD player 
products are now available. 

ELECTRONICS Australia, September 1998 


were to begin in the second quarter of 1998. 

Poised to gain a competitive advantage 
by being the first to announce volume 
shipments, Philips is prepared for the high 
market demand of PC-DVB Receivers. 
The Philips CleverCast PC solution is 
claimed to be compatible with every IP 
based application. Applications such as 
Precept Software’s IP/TV, StarBurst, 
Microsoft NetShow, Philips Broadcast 
FTP and services from DataCast and The 
Fantastic Corporation are said to run 
seamlessly on the platform, with 
CleverCast PC’s adherence to both broad¬ 
casting standards (DVB SI-Dat) and 
Intemet/PC standards (TCP-IP, Microsoft 
Windows 95/NT). 

To date, Philips has successfully sup¬ 
plied complete end-to-end solutions, from 
uplink equipment to PC-DVB Digital 
Receivers and DVB compliant Data 
Broadcasting Systems — to such presti¬ 
gious international broadcasters as 
Deutsche Telekom (Germany), Teracom 
(Sweden), Telenor (Norway), RAI (Italy) 
and Digital Express (USA). 

The CleverCast PC Data Broadcasting 
System allows for the reception of digital 
multimedia data (audio, video and data) 
which is broadcast at high speeds through 
digital satellite transmission systems to per¬ 
sonal computers. This application makes it 
possible to transmit data in a digital form to 
a single user (unicast), a group of users (mul¬ 
ticast), or to all users with access to the ser¬ 
vice (broadcast). The platform can be used 
for new services such as Broadcast File 
Transfer and High Speed Internet. 

High-speed data broadcasting to the PC, 
currently available at a rate of 16Mb/s, will 
be available at an increased rate of 45Mb/s 
before the end of 1998. Since the data, usu¬ 
ally in a compressed form, need only be 
transmitted to the satellite network once, this 
data ‘push’ method saves bandwidth and 
reduces transmission costs drastically. 

Intel introduces 
Pentium II Xeon 

Intel Corporation has introduced a new family 
of processors designed to meet the demanding 
requirements of mid-range and higher servers 
and workstations. The new Pentium II ‘Xeon’ 
processors feature technical innovations 
specifically designed for workstations and 
servers which run demanding business appli¬ 
cations such as Internet services, corporate 
data warehousing, digital content creation, 
electronic and mechanical design automation. 

The Pentium II Xeon processor delivers 
industry leading performance from its larger 
and faster Level 2 (L2) caches, multiprocess¬ 
ing capabilities and a 100MHz system bus. 
Systems based on the Pentium II Xeon can be 
configured to scale up to four or eight proces¬ 
sors and beyond. The combination of the pure 
performance of the Pentium II Xeon proces¬ 
sor and this scalability are claimed to bring 
exceptional levels of price performance to the 
server and workstation market segments. 

Intel claims Pentium II Xeon processor- 
based servers deliver the industry’s best 
four-processor TPC-C result to date, with a 
rate of 18,127.40 tpmC running on 
Compaq’s ProLiant 7000 6/400 with 
Microsoft Windows NT4.0 and SQL 
Server 7.0. (The benchmark measures the 
rate of common database transactions in an 
online transaction processing environment 
such as a customer service call centre). 

Key features of the Pentium II Xeon 
processor include a 0.25 micron P6 microar¬ 

chitecture core featuring Dynamic 
Execution, operating at 400MHz; 512KB and 
1MB L2 cache options; Intel’s Dual 
Independent Bus featuring a 400MHz L2 
cache bus, operating at the same speed as the 
processor core, a 100MHz transactional 
System Bus and 100MHz SDRAM and EDO 
memory support, allowing faster communi¬ 
cation between the processor and other parts 
of the computer system; support for greater 
than 4GB of memory for servers using Intel’s 
Extended Server Memory Architecture; and 
addressable memory support up to 64GB. 

DKD accredits 
Fluke calibrators 

Fluke Corporation claims it has become the 
first US electronics manufacturer to receive 
accreditation for both its standards laboratory 
and calibrator production facilities by 
Germany’s Deutscher Kalibrierdienst (DKD), 
the laboratory accreditation body of the 
German national standards organization. The 
accreditation allows Fluke to provide globally 
recognized, legally traceable test data for 
most Fluke calibrators, eliminating the time 
and expense to re-calibrate instruments 
shipped to users outside the United States. 

According to Fluke standards laboratory 
manager, Ray Kletke, this accreditation is 
something of a landmark. “This is the first time 
anyone in the US has worked with a member 
of the European co-operation for Accreditation 
(EA). It involved a lot of collaboration between 
Fluke and the national standards organizations 






• The postal address for computer-aided 
design tools specialist Protel 
International has changed; it’s now PO 
Box 427, Frenchs Forest 1640. 

• Frequency control product supplier Hy-Q 
International (Australia) has changed its 
email address, which is now sales@hy- 

• Software and computer peripherals dis¬ 
tributor Dataflow Computer Services 
has appointed former Philips Australia 
Chairman and CEO Justus Veeneklaas 

to its board of directors. 

• Technical training specialist TTC Australia 
has introduced technology training 
courses which can be supplied as either 
cost effective computer-based packages 
or professionally run courses. Courses 
available during September 1998 
include 2M Transmission Fundamentals, 
Frame Relay Technology & 
Implementation, ATM Technology & 
Implementation, ISDN Fundamentals & 
Implementation, and An Introduction to 

LANs and Internetworking. For more 
information contact TTC on (03) 9563 
4800 or (02) 9926 1447. 

• SMT China V8, the 2nd China 
International Surface Mount Technology 
Exhibition, will be held September 22- 
25 at the INTEX International Exhibition 
Centre in Shanghai. For more informa¬ 
tion contact organisers Messe & 
Kongress GmbH in Stuttgart, Germany; 
fax (+49 711) 66197-79. ❖ 


ELECTRONICS Australia, September 1998 

of the US and Germany.” 

The Fluke production facility is accredited as 
an extension of the corporate standards labora¬ 
tory, so each final test system on the production 
line falls under the lab’s responsibility. Each 
system is highly automated, eliminating most 
manual intervention in the final test stages. 
Finally, all stations are monitored continuously 
as part of a statistical process control loop. 

AMD to deliver 
chip for HomePNA 

AMD, a founding member of the Home 
Phoneline Networking Alliance (HomePNA), 
has announced that it will deliver single chip, 
low-cost silicon implementations based on the 
Alliance’s initial IMb/s specification for tele¬ 
phone wire networking. Production samples 
will be available for integration onto mother¬ 
boards, circuit boards, network interface cards 
and other consumer electronics devices during 
the Q4 of 1988. 

The HomePNA is a consortium of the lead¬ 
ing computing and communications compa¬ 
nies, working together to ensure the adoption 
of a single, unified phone line networking 
standard. The HomePNA has adopted a robust 
technology based on existing Ethernet stan¬ 
dards to support the use of telephone wiring to 
network computers, peripherals and digital 
devices throughout the home. 

“AMD is committed to helping the 
HomePNA drive industry standards for 
phone line networks capable of meeting the 
growing requirement within the home for 
easily deployed networking capabilities,” 
said Tom Eby, Group VP of AMD’s 
Communications Group. 

Founding members of the HomePNA 
include 3Com, AMD, AT&T Wireless, 
Compaq, Epigram, Hewlett-Packard, IBM, 
Intel, Lucent, Rockwell and Tut Systems. 
Further HomePNA information is available on 
the World Wide Web at 

P&G transducers 
help launch Ariane 5 

Four different types of linear displacement 
transducers (LVDTs) made by control tech¬ 
nology specialists Penny & Giles have been 
used in the European space program. The 

LVDTs were used on the solid boosters, the 
first stage Vulcain engine and the second stage 
Aestus engine of the Ariane 5 launch vehicle. 

LVDTs are installed on the direct drive 
valves and servo actuators used for both the 
thrust vector control of the solid boosters and 
the Vulcain engine of the first stage; and the 
Aestus engine of the second stage. The LVDTs 
for the solid boosters and Vulcain engine were 
supplied to SABCA (Societe Anonyme Beige 
de Constructions Aeronautiques) of Belgium, 
who were involved in the design and manufac¬ 
ture of direct drive valves and servo actuators 
for the project. 

Penny & Giles were introduced to SABCA 
by their Belgian distributor EIG Benelux, and 
were selected to supply LVDTs for the Ariane 
5 servo actuators following an engineering 
development programme to produce qualified 
product to SABCA’s specifications. The com¬ 
pany received its first order for the project in 
1989 and their LVDTs made it into space with 
the successful launch of mission 502 from 
Kourou, French Guyana on 30th October 1997. 

A third Ariane 5 launch is scheduled for 
Summer 1998 and commercial launches are 
expected to begin in the second half of 1998. 

More information is available on Penny & 
Giles products from distributor Control 
Devices, on (02) 9356 1943. 

Growth expected 
in flat panels 

Although the North American market for 
portable computers is the world’s largest, 
most displays are incorporated into comput¬ 
ers overseas, mainly Taiwan. The fastest and 
most profitable growth is expected to be in 
applications other than portable computers. 
Major manufacturers are now targeting 
emerging markets such as flat panel display 
(FPD) monitors and non-portable TVs. 

According to strategic research conducted 
by Frost & Sullivan ( and 
presented in the report North American 
Commercial and Consumer Electronics Flat 
Panel Display Markets , the total market is 
expected to reach almost US$9.5 billion in 
2004. As prices become viable, the FPD 
monitor market and non-portable FPD TV 
market are expected to grow the fastest. 

The improvement of established technolo¬ 
gies and the development of new ones are 
major drivers in the FPD market. New tech¬ 
nologies including plasma, field emission dis¬ 
plays (FED) and digital micromirror devices 
(DMD), as well as improvements in liquid 
crystal displays, are expected to create new 
markets and challenge existing technologies. 

“The major concern for market partici¬ 
pants is achieving low price through cost 
effective manufacturing”, says Frost & 
Sullivan Analyst Jouni Forsman. Currently, 
FPD prices are too high to allow for the max¬ 
imum attainable market penetration. ❖ 

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printing, online PCB quotes, NC 
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plastic and aluminium cases, 
prototype PVC cases made to order. 
Many other items and services at 
Ph: (02) 9743 9235, 

Logic Analyser lOOMs/s 32-Channel 
Kit $1275. Stand alone, not a plug in 
PC Card. Requires a VGA or EGA 
monitor - user supplied. Edge and 
Level Triggering. Multiple Triggering 
Modes such as, Trigger on pulse 
width too long or too short, Clock 
Stop, User Defined Storing, 2 Level 
Storing, 2 Level sequencer. 

Request brochure from: Peter Baxter, 
Tantau Australia, PO Box 1232 
Lane Cove 1595, Sydney. 

Ph: 02 9878 4715. Fx: 02 9888 7679. 
All manuals of the website: 
Revised, no prototype area, “8051 
Proto-Board” EA Feb 93. $30. 


0.1 |jH - 200H 
0.1 pF ~ 20,000pF 
1 mfi ~ 20MQ 


Corporation Ltd 

6 Sarich Way. Technology Park, Bentley, WA, 6102 
Ph 08 9470 1177 Fax 08 9470 2844 
Specifications at 

Early and vintage HiFi, amplifiers, 
turntables, speakers, valves, pre 1969. 
Cash paid (07) 5449 1601 
OLD video recordings of TV Station 
broadcasts from 1956 to 1980. 
T.Ernslie, 13 Warren St, Ryde 2112. 
Ph: (02) 9888 2062. 

WW II Army Suitcase Transmitters, 
Receivers, Type A. Mark III + Type 3. 
Mark II, & MCR 1, RX. A.W.A. AMR 
100 RX. No.11, 19, 22, Sets or Part 
Sets, any condition. Pay reasonable 
price, Ray VK4FH. PO Box 5263 Daisy 
Hill, Brisbane. Ph: (07) 3299 3819. 

Fax: (07) 3299 3821. 

ELECTRONICS Australia, September 1998 


Solid Stat<L,,„ 

Keeping you informed on the latest developments in semiconductor technology 

Analog CCD and CIS 
signal processor 

Analog Devices has released the AD9816, 
a 12-bit, 6MS/s Analog-Front-End (AFE) 
that integrates an analog to digital convert¬ 
er (ADC) with the analog circuitry needed 
for three-channel (RGB) image condition¬ 
ing and sampling. The AD9816 can be 
programmed through a serial interface, 
and also includes an input pin for offset 
adjustment that will give users greater 
flexibility to use any type of CIS sensor 
currently on the market. 

The AD9816 will perform all the signal 
processing necessary for applications such 
as mid- to high-end desktop scanners, dig¬ 
ital still cameras, medical X-rays, security 
cameras and any instrumentation applica¬ 
tions that ‘read’ images from CCD and 
CIS sensors. 

The signal chain of the AD9816 consists 
of an input clamp, correlated double sam¬ 
pler (CDS), offset adjust DAC, programma¬ 
ble-gain amplifier and a 12-bit CMOS ADC 
core. It has been designed to run at 6MS/s 
with good linearity and noise performance 
and to guarantee no missing codes at maxi¬ 
mum conditions — while running at 6MHz 
in three-channel CDS mode. 

The AD9816 has a DNL of+/-0.33LSB. 
At gain = lx noise is only 0.5 LSB RMS. In 
fact, even at gain = 6x the noise is only 0.8, 
which is far superior to the AD9816’s clos¬ 
est competitor. Crosstalk on the AD9816 is 
less than 1 LSB. 

The AD9816 operates from a 5V supply 
and typically consumes just 500 mW of 
power. For more information circle 271 on 
the reader service card or contact Analog 
Devices, PO Box 2098, Rosebud Plaza 3939. 

Multimode Ultra2 
SCSI terminator 

A new multimode SCSI terminator that holds 
termination resistance more closely to the 
110-ohm spec than comparable devices is 
available from Dallas Semiconductor. Fully 
compliant with emerging Ultra2 SCSI speci¬ 
fications, the DS2118M is a multimode, low- 
voltage differential/single-ended (LVD/SE) 
Ultra2 SCSI terminator that provides active 
termination for nine signal line pairs. 

Because Dallas laser-trims resistor ladder 
structures within each device, the DS2118M 
can hold the SCSI-specified 110-ohm termi¬ 
nation resistance to +/-5%. Comparable 
devices show a tolerance of +/-8%. 

“As a multimode SCSI terminator, the 
DS2118M contains circuitry that determines if 
a bus requires SE or LVD termination,” said 
Charles Tashbook, product manager. “The 
chip automatically selects the proper mode.” 

The DS2118M has a low power-down 
capacitance of 3pF and on-chip thermal 
shutdown circuitry. 

For more information contact Dallas 
Semiconductor, 4401 S. Beltwood Parkway, 
Dallas Texas 75244-3292 USA. 

‘Smallest 500mA 
LDO regulators 

Micrel Semiconductor has announced its 
new 500mA range of low power, low 

dropout (LDO) regulators, the M1C5219 
and M1C5216. Both devices are available in 
power MSOP-8 and Micrel’s TttyBitty’ 
SOT23-5 packaging, claimed to make them 
the industry’s smallest 500mA regulators. 

Micrel’s power MSOP-8 package has a 
fused leadframe to improve thermal resis¬ 
tance, providing it with the power handling 
capabilities similar to a much larger SO-8 
package. Power dissipation constraints typi¬ 
cally limit output current in SOT23-5 
devices to less than 150mA. The M1C5219 
and MIC5216 provide 500mA capability for 
applications with occasional or periodic 
demand for high current; these applications 
have previously required much larger prod¬ 
ucts in SO-8 packaging. 

The M1C5216 and M1C5219 are suited 
for mobile applications where small size and 
high efficiency are critical. Low dropout 
voltage of 300mV at 500mA, low quiescent 
current of 80uA and a shutdown pin extend 
battery life, while in shutdown, the devices 
have a near-zero supply current. Tight initial 
accuracy of 1% and excellent line and load 
regulation ensure a precise output voltage. 

Both the MIC5219BM5 and MIC5216BM5 
are available with adjustable or fixed output 
voltages of 3.0V, 3.3V, 3.6V or 5.0V. 

For more information circle 272 on the 
reader service card or contact GEC 
Electronics Division, Unit 1, 38 South 
Street, Rydalmere NSW 2116. 

16-bit DAC with 
serial micro interface 

Burr-Brown’s new DAC716 is a high resolu¬ 
tion, monolithic 16-bit digital-to-analog con¬ 
verter (DAC) with serial microprocessor inter¬ 
face, specified for industrial process and con¬ 
trol applications such as robotics, motor speed 
control, and equipment motion controllers. 

The DAC716 is complete with an internal 
+10V temperature compensated voltage refer¬ 
ence, current-to-voltage amplifier, a high¬ 
speed synchronous serial interface, a serial out¬ 
put which allows cascading multiple convert¬ 
ers, and an asynchronous-clear function which 
immediately sets the output voltage to zero. 

The output voltage range is 0 to +10V 
while operating from +/-12V to +/-15V sup¬ 
plies, and the gain and bipolar offset adjust¬ 
ments are designed so that they can be set via 
external potentiometers or external DACs. 
The output amplifier is protected against 


ELECTRONICS Australia, September 1998 

short-circuiting to ground. 

Other features include 600mW power 
dissipation, fast settling time (lOus to 
0.5LSB), and 15-bit monotonic perfor¬ 
mance over temperature. 

For more information circle 273 on the 
reader service card or contact Kenelec, 2 
Apollo Court, Blackburn 3130. 

Triple 140MS/S ADC 
for SXGA LCD monitors 

Analog Devices has introduced the AD9483, 
a triple 8-bit analog-to-digital converter 
(ADC) that has been optimized for digitizing 
RGB graphics signals from personal com¬ 
puters and workstations, as needed to drive 
LCD monitors. 

With a 140MS/s encode rate and full-power 
analog bandwidth of 300MHz, the AD9483 
can support display resolutions up to 1280 x 
1024 at 75Hz, with sufficient input bandwidth 
to accurately acquire and digitize each pixel. 
These features, along with a 1V peak-to-peak 
analog input range and low power dissipation 
(less than 1.5W at +5.0V) makes the AD9483 
very suitable for RGB graphics processing for 
LCD monitors, graphics projectors, and plas¬ 
ma display panels. 

To minimize the user’s system cost and 
power dissipation, the AD9483 includes an 
internal +2.5V reference and track-and-hold 
circuit. All the user has to do is provide +5V 
and an encode clock — which means that no 
external reference or additional drive circuit¬ 
ry will be needed for many applications. 

The encode input of the AD9483 inter¬ 
faces directly to TTL, CMOS, or positive- 
ECL logic, and will operate with single- 
ended or differential inputs. The digital out¬ 
puts are three-state CMOS and may be pow¬ 
ered from either a +3.3V or +5V supply. 

For more information circle 274 on the 
reader service card or contact Analog 
Devices, PO Box 2098, Rosebud Plaza 3939. 

Dual channel 20-bit 
delta-sigma ADC 

Burr-Brown’s new DDC 112 is a dual input, 
wide dynamic range, charge digitizing ana¬ 
log-to-digital converter (ADC) with 20-bit 
resolution. It is designed to accept low-level 
input currents from direct photosensor digi¬ 
tizer applications such as CT (computed 
tomography) scanners, infrared heat detec¬ 
tors, liquid or gas chromatography, and 
blood analysis. 

The DDC 112 combines the functions of 
current-to-voltage conversion, integration/ 
input programmable full scale gain amplifi¬ 
cation, A/D conversion, and digital filtering 
to produce precision, wide dynamic range 
digital results. Charge integration is contin¬ 
uous as each channel contains two integra¬ 
tors — while one is being digitized, the 
other is integrating. 

The device offers the ability to use 

external integrating capacitors, thus allow¬ 
ing a user-programmable full-scale range 
up to lOOOpC. In addition, the serial I/O 
register can be configured to allow multi¬ 
ple DDC 112 units to be cascaded, mini¬ 
mizing interconnections. Other features 
include single supply operation, integral 
linearity (+/-0.005% reading +/-0.5ppm 
FSR), and digital filter noise reduction 
(3.2ppm RMS). 

For more information circle 275 on the 
reader service card or contact Kenelec, 2 
Apollo Court, Blackburn 3130. 

MCU support 1C 
has 3000 gate CPLD 

WSI’s latest addition to its family of flash 
MCU support ICs, the PSD8XXF2 inte¬ 
grates high-density (serial or parallel pro¬ 
grammable) concurrent flash memory with 
complex programmable logic, SRAM, 
extra I/O and a programmable microcon¬ 
troller interface. 

The PSD8XXF2 allows flash memory 
erase/write operations to be performed dur¬ 
ing program execution by providing two 

flash memory arrays of 128K and 32K bytes. 
The 128KB flash array is used for system 
program store and the 32KB (four 8KB sec¬ 
tors) array is used to store boot algorithms, 
programming algorithms and NVM data. 
Since the system can execute code from 
either flash array, each can be programmed 
concurrently with system operation. 

In addition to the two ISP flash arrays, 
the PSD8XXF2 has a 2KB scratchpad 
SRAM, a 3000 gate Micro-Cell CPLD, a 
special ISP decoding PLD, extra I/O and a 
programmable interface to most microcon¬ 
trollers from Philips, Intel, Motorola, 
Siemens and others. A JTAG interface is 
provided for first-time and subsequent ser¬ 
ial ISP that is six times faster than parallel 

For more information contact WSI, 47280 
Kato Road, Fremont 94538 California, USA. ❖ 



Microphone, Line and Splitting 
Video Isolation 

Vacuum Tube Drive & Output 

Control Devices 

Phone: (02) 93561943 
Fax: (02) 93561908 

ELECTRONICS Australia, September 1998 




Claimed to be the smallest yet, the recently introduced GSC20 
compact 20W switching power supply from Powerbox is very suit¬ 
able for overhead projectors, data communications devices and 
any application needing a compact, portable and reliable power 
source. It has a footprint no bigger than a business card, measuring 
87.5 x 50 x 17.2mm, but delivers an output of 4W/in'. 

With an input voltage range of 90 - 264V AC, the GSC20 has 
fixed frequency operation and standard overvoltage protection, 
and complies with EMI FCC Class B, CISPR22B. It is approved to 
UL1950, IEC950, CSA 22.2 No.234 Level 3 and EN60950. 

The GSC20 is available in five versions, with power levels from 
5 to 28 volts and carries a two-year warranty. Medical configura¬ 
tions are available on request. 

For more information circle 241 on the reader service card or con¬ 
tact Powerbox Australia, 4 Beaumont Road, Mt Kuring-gai 2080. 

Handheld tester finds comms cable faults 

The new Tektronix TV90 CableScout time domain reflectometer 
(TDR) is a low-cost, high performance handheld instrument for 
maintaining and installing communications cabling systems. 
Outside plant technicians and installers in the cable television 
(CATV) industry can use the instrument to locate and troubleshoot 
cable faults in new or existing coaxial drop cable. 

The TV90 
easy-to-use one- 
step setup and 
two-step test 
ensures quick 
results, reducing 
repair time. 

Technician train¬ 
ing time is also 
decreased with the 
help of a simple 
user interface. 

The instrument 
can test cable dis¬ 
tances greater than 
4000 feet and pro¬ 
vides distance accuracy to +/-2 feet. It is weather-proofed for 
operating temperatures of 0 to +45°C with 95% humidity. It is 
also easily portable, weighing only 1kg and measuring just 211 x 
141 x 43mm. 

For more information circle 242 on the reader service card or 
contact Tektronix Australia, 80 Waterloo Road, North Ryde 2113. 

PC-based power analyser 

The EasyPower Measure is a first-of-its-kind, PC based power 
measurement instrument that can be used as a user-interactive 
three-phase power analyser or a stand-alone power-quality mon¬ 
itor. At a fraction of the price of other full featured analysers, 
the portable system provides real-time waveform display and 
data management using the familiar graphical user interface and 
intelligence of a notebook PC, which eliminate the blind collec¬ 
tion and disorganised information storage associated with typi¬ 
cal power analysers. 

With the EasyPower Measure system, the PC is the instru¬ 
ment. The measurement front-end supplies the voltage and cur¬ 
rent data directly to a notebook PC in real time via four voltage 
inputs (1250V peak differential via sheathed banana safety con¬ 
nectors) and four current clamp inputs. As data is collected, the 
PC performs all of the power calculations, provides graphics and 
numeric tables, and stores the data to its hard drive in real time. 
Data collection accuracy is +/-0.03% for both current and volt¬ 
age and measurement resolution is 12 bits. Sample frequency is 
128 samples per cycle nominal and 256 points per cycle maxi¬ 

mum, while the maxi¬ 
mum single-channel 
sample rate is 500kHz. 

The EasyPower 

Measurement platform 
offers five power mea¬ 
surement modes. The 
Phasor Diagram mode 
comes standard with the 
EasyPower Measure; 
Detailed Harmonics, 
Spectrum Analyser, 
Cycle-by-Cycle and 
Event/Demand Capture 
measurement modes are 
available options. With 
all of these modes, wave 
shapes, calculated waveforms and numeric tables can be easily 
viewed on the PC’s monitor in real time. 

For more information circle 246 on the reader service card or 
contact Scientific Devices Australia, 118 Atkinson Street, 
Oakleigh 3166. 


ELECTRONICS Australia, September 1998 

RF chokes for PCB mounting 

The new Schaffner RN-series chokes are designed to provide high 
attenuation of common mode interference in the range of 100kHz 
to 3MHz, while differential mode signals in the operating range of 
the chokes (DC - 1kHz) encounter zero inductance. Typical appli¬ 
cations include uninterruptible and switch-mode power supplies, 
DC-DC converters, etc. 

The RN series employ toroidal ferrite cores, offering a very high 
inductance to volume ratio. Dual current-compensated windings 
prevent core saturation when handling large peak currents. 

The chokes are available for load current ratings from OJA to 
10A with a voltage rating of 250V, and with path inductances 
ranging from 0.7mH to lOOmH. They are well suited to PCB 
mounting, being available in low-profile or small footprint 
housings. The RN chokes are manufactured to rigorous quality 
control standards, and withstand winding-to-winding and wind¬ 
ing-to-housing voltages of 1500V and 4000V AC respectively, 
for one minute. 

For more information circle 243 on the reader service card or 
contact Westek Industrial Products, Unit 2, 6-10 Maria Street, 
Laverton North 3026. 

Hall effect AC/DC high current sensors 

The L series range of Hall effect current sensors from Practical 
Control Solutions are suitable for measuring currents from 500 - 
2000 amps at frequencies from DC to 10kHz. The bipolar output 
is +/-4V DC full scale, with a positive voltage for positive current 
flow. A +/-15V 30mA DC power supply is required, which is also 
available from PCS. 

Unlike shunts the Hall effect sensors are fully isolated from the 
DC bus, allowing the use of grounded control equipment. Also no 
heat is dissipated across the Hall effect sensor, making the cooling 
measures required for high current shunts unnecessary. 

For more information circle 244 on the reader service card or 
contact Practical Control Solutions, PO Box 1052, Mount 
Waverley Delivery Centre, Mount Waverley 3149. 

Handheld El tester 

TTC Inc’s TTC 132B Communications Analyser is designed to 
help field installation and maintenance by combining El (2Mb/s) 
analysis features into a compact and rugged instrument. The 
instrument’s Auto Configuration feature provides quicker and 
easier instrument setup by determining and synchronising to the 
framing format and pattern, thus automatically configuring to the 
signal under test. 

Easy to read Results Summary indicators provide instant 
information to the user about circuit status. With this informa¬ 
tion available at the user fingertips, circuit problems are effi¬ 
ciently identified and sectionalised. For long term unattended 
testing in the field, the TTC132B offers event-print and timed- 
print outputs. 

Additional highlights of the instrument include an active 
timeslot display for simple identification of channel activity, as 
well as results summary and front panel LED’s that offer imme¬ 
diate indication of critical circuit parameters such as error events, 
alarm conditions, and configuration status. 

The TTC132B is available immediately and will sell in Australia 
and New Zealand for under A$7000. 

For more information circle 245 on the reader service card or 
contact TTC Australia, 41 Stamford Road, Oakleigh 3166. ❖ 

Don’t take our word for it... this is what Jim Rowe said! 

“Well worth serious 
consideration if you’re after 
good quality at a less than 

premium price. 


jn e Mw 

<CIE 125 Low Cost DMM 

• 3200 count 

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• Auto Power off 

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True RMS; CIE125C 
has pF instead of A. 

CIE128 Automotive DMM> 

• 3200 count 

• RPM,dwell, duty 
cycle, pF, temp, freq 

• Vdc, Vac, Q, 10A 

• Auto off 

< CIE 8088 Automotive DMM 

• 3999 count 

• RPM, pulse,dwell, 
duty cycle, pF, temp, freq 

• Vdc, Vac, Q, 20A 

CIE 8042N Temperature DMM> 

• 3200 count 

• Temp-20 to 750°C, 

• Vdc, Vac, Q, 20A 

• Warning beeper 

< CIE CA-60 Current Clamp Adapter 

• Converts mA to mV, ac/dc 

• Use 200mV/2V DMM ranges 

• 60 A max, 9mm jaw 

CIE 2608 AC/DC Current Clamp Meter > 

• 57mm(0)/7Ox18mm jaw 

• 1500Aac/2000Adc, 3999 count 

• Vdc, Vac, Q, pF.freq 

• Max/Min/Peak Hold 

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• 3V2 digit, ±3%/3°C accuracy 
- • Measures from -20°C to +260°C 

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• 65mmo field of view @ 1 m 

• Also available as DMM probe (61LC) 

All these meters are supplied with safety test leads, spare fuses (where 
applicable and holsters. Available from selected electrical and electronic 
distributors or visit our trade counter. 

Call us for FREE brochures and unbiased advice 
on the best meter for your application! 

We also carry a full range of FLUKE multimeters, Scopemeters and accessories 
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129 Queen Street, Beaconsfield. Any prices quoted are ex-tax 

P.O.Box 37 Beaconsfield NSW 2014 acn : 003166 952 

Tel: (02) 9698 4111 Fax: (02) 9699 9170 

Call for name of your local stockist 


AT&T buys TCI for US$48 billion 

IN YET ANOTHER mega merger in the telecommunications industry, AT&T 
announced it has agreed to pay a whopping US$48 billion for America’s largest 
cable TV operator, Tele-Communications Inc (TCI). The deal opens the way for 
AT&T to offer 33 million consumers and businesses a one-stop shopping option 
for a broad range of services, from cable TV to home shopping to high-speed 
Internet access and local and long distance telephone calls. 

AT&T said it will set up a new company, to be known as AT&T Consumer 
Services, which will offer one-stop shopping for long-distance and cellular phone 
calls, cable television and high-speed Internet access. “We are merging with TCI 
not just for what it is, but for what we can become together”, said AT&T chairman 
Michael Armstrong. John Malone, chairman of TCI, has agreed to become a 
member of the AT&T board. 

Armstrong joined AT&T only last year. The TCI deal is the biggest in a series of 
aggressive moves he has made in his short tenure. In late 1997, he bought 
Teleport Communications Group for US$11.3 billion and recently AT&T said it 
would lay off 18,000 people. He has also forged marketing alliances with several 
Internet search companies. 

TCI will now allow AT&T to provide local telephone service using TCI’s cable 
TV network instead of using traditional phone lines. That gives AT&T a crucial, 
direct link to consumer’s homes bypassing the Baby Bells’ infrastructure altogeth¬ 
er. “Today we’re beginning to answer a big part of the question about how we will 
provide local service to US consumers”, Armstrong said. 

Tl sells its 
DRAM business 

of the volatile memory chip market, Texas 
Instruments has sold its memory chip busi¬ 
ness unit to the only other American DRAM 
producer, Micron Technology for US$800 
million. TI also said it will lay off 3500 
workers due to continued weakness in the 
overall semiconductor market. The lay-off, 
about 8% of the company’s global work¬ 
force, will save the company US$270 mil¬ 
lion in annual operating expenses. 

TI officials said the company is ridding 
itself of the memory operations at a consid¬ 
erable loss. But prospects for a return to prof¬ 
itability appear so dim right now, TI believes 
it stands to lose far more if it has to continue 
making heavy R&D and capital investment 
commitments to the memory field. 

As part of the transaction, Micron will get 
a number of state-of-the-art chip production 
facilities in Italy, Singapore and Richardson, 
Texas. TI will also close a second Richardson 
operation with Micron getting the building. 

The sale to Micron does not come unex¬ 
pected. For much of the past year, TI has 
been reducing its committment to the memo¬ 
ry business, including selling or abandoning 
memory business interests in joint ventures 
with Taiwan’s Acer and Japan’s Hitachi. 
Instead TI is focusing its semiconductor 
business on digital signal processors and 
other high-end circuits where there is consid¬ 
erably less competition or pressure on prices. 

Is DVIX dead? 

DVIX, A CONSUMER technology that 
competes with standard DVD video, appears 
on its last legs as sales of DVIX players and 
disks have been lacklustre. Several major US 
distribution retail chains are said to be close 
to pulling out of the DVIX business and 
focus on DVD instead. 

DVIX allows consumers to purchase a 
digital video disk for around US$5, com¬ 
pared to US$20 for regular DVD titles. But 
users have to pay about US$3 for each 
viewing. Consumers in the US have so far 
shown a much stronger preference towards 
owning DVD movies outright, or paying 
about $3 to rent them from a local video and 
DVD rental store. 

Meanwhile, 20th Century Fox Studios 
announced it is going to market DVD 
movies, after holding out on the DVD busi¬ 

ness until now. The home video units of Walt 
Disney and Time Warner have also 
announced that they are banding together in 
an international DVD distribution pact. 
Under the deal, Warner Home Video will 
distribute DVD movies from Buena Vista 
Home Video, the Disney unit, in 30 territo¬ 
ries spread across Europe, the Middle East, 
Africa and in former Soviet Union countries. 
The agreement covers over 100 titles and 
runs through the year 2000. Each of the 
movies will be released simultaneously in 
DVD and on videotape in the VHS format. 

Rockwell quits 
the chip business 

US producer of communications and other 
ICs, said it is spinning off the chip business 
into a separate company and laying off some 
3800 workers in the process. The move is 
expected to cost Rockwell US$625 million 
in write-offs. 

“The dynamics of semiconductor systems 
are very different from Rockwell’s other 
businesses, including its markets, products, 
and investment requirements”, said 
Rockwell chairman Don Davis in explaining 
the decision. “Splitting the companies will 
help Rockwell enhance their ability to 
achieve their full potential”, he added. 

The elimination of the IC operations fol¬ 
lows a 1996 decision to sell the firm’s 
defense and aerospace operations. And a 
year ago, Rockwell also spun off its automo¬ 
tive parts operations. 

The IC spinoff is expected to be complet¬ 
ed by the end of the year. The company’s full 
restructuring program will be completed by 
the end of 1999. 

LSI buys Symbios 
as Adaptec bows out 

SYMBIOS HAS YET another parent compa¬ 
ny, as LSI Logic announced plans to pay 
US$769 million to Hyundai Electronics. 
Earlier this year Adaptec, located just one 
block down the street from LSI Logic in 
Milpitas, had agreed to pay US$775 million 
agreement for Symbios. Adaptec said it did¬ 
n’t expect the US Federal Trade Commission 
to approve the merger and was ending the 
merger process. 

LSI officials said their company had been 
one of several companies that bid on 
Symbios. Hyundai initially chose Adaptec. 
The FTC, however, objected, stating the 
Adaptec/Symbios merger would concentrate 
too much of the data communications inter¬ 
face market with one vendor. 

The Symbios acquisition means LSI will 
be able to offer its customers SCSI technolo- 


ELECTRONICS Australia, September 1998 

gy. “This major acquisition reflects our strat¬ 
egy of further penetrating the high-end com¬ 
puting and storage markets”, said Wilf 
Corrigan, LSI Logic chairman and chief 
executive. “This is the largest acquisition in 
the history of LSI Logic. LSI goes from 
being a US$1.3 billion company to being a 
$2 billion company.” 

Symbios is based in Fort Collins, 
Colorado. The company makes client/server 
ICs, host adapter boards and similar compo¬ 
nents. The company had 1997 revenues of 
US$620 million and operating income of 
$70 million before non-recurring charges. 

AT&T, which acquired Symbios in the 
NCR merger, sold Symbios to Hyundai in 
1995. At that time, Adaptec was among the 
bidders for the unit. 

Motorola loses $1.3Bn 

MOTOROLA’S TINY US$6 million operat¬ 
ing profit was overshadowed by $1.9 billion 
in corporate restructuring charges that 
caused the firm to report a net loss of US$1.3 
billion. A year ago, it earned $392 million. 

The impact of the Asian crisis, which is to 

blame for most of Motorola’s woes is likely 
to continue for at least another year, said 
CEO Christopher Galvin. 

Compaq begins 
its restructuring 

MAJOR LAY-OFF announcements are start¬ 
ing to come out of Compaq on a weekly 
basis, in the wake of the Digital Equipment 
merger and increasing softness in the person¬ 
al computer market. Compaq said it is firing 
5000 additional workers and closing eight 
facilities around the world as part of the 
assimilation of Digital. The 5000 are part of 
the total of 17,000 jobs, which are expected 
to be lost as a result of the merger, a com¬ 
bined workforce reduction of 20%. The com¬ 
bined company will have about 67,000 work¬ 
ers when the consolidations are completed, a 
process that will cost Compaq some US$5.4 
billion in charges against its earnings. 

The company is expected to save several 
billion dollars year in operating expenses as 
a result of the restructuring. “Integrating all 
Compaq manufacturing operations into a 
single, cohesive organization is essential as 

we build the future Compaq”, said Compaq 
CEO Eckhardt Pfeiffer. “It is important to 
say that the loss we expect is different than 
the operational result. This charge is posi¬ 
tioning the company for the future.” 

Pfeiffer insisted that customers will bene¬ 
fit from the streamlining, which is aimed at 
allowing Compaq to deliver 95% of its prod¬ 
ucts anywhere in the world in less than five 
days. Currently it can take weeks, because 
the company ships through distributors and 
others who add to the time it takes to get the 
product to the end user. 

Gates alone at the 
top with US$51 B 

Not surprisingly, Bill Gates once again 
topped Fortes Magazine's list of the world’s 
richest and actively working individuals. The 
magazine put Gates’ net worth at US$51 bil¬ 
lion, up 40% from a year ago. 

Gates came within one bad day on Wall 
Street of losing the title he has held for four 
years, to the heirs of the late Sam Walton, 
founder of the Wal-Mart chain of discount 
superstores. They’re worth US$48 billion. ♦> 

Will Apple bounce back with the iMac? 

APPLE’S NEW IMAC computer took centre stage at the 
recent MacWorld Expo in New York, and is expected to help 
Apple report high sales and earnings in the next quarter. 
Analysts expected Apple to ship as many as 400,000 iMacs 
in the quarter ending in September. 

A reviving Apple is also expected to report its third con¬ 
secutive quarterly profit for the period that ended June 30, 
driven by strong demand for G3 systems, said CEO Steve 
Jobs during an unscheduled keynote address at the 
MacWorld show. “I am very pleased to tell you that it will be 
our third consecutive profitable quarter”, said Jobs, who was 
greeted with a thunderous standing ovation. Jobs said Apple 
is putting new efforts behind supporting its customer base in 
traditional Macintosh strongholds, such as desktop publish¬ 
ing, education and design. 

A year ago Jobs and Microsoft chief Bill Gates were 
booed at the then Boston-based MacWorld, when the two 
announced Microsoft’s US$150 million investment in Apple 
in return for stock and Internet Explorer becoming the 
default browser on the Mac platform. Jobs said the program 
has done wonders for Apple and the firm is working hard to 
further strengthen its ties with Microsoft. “Despite the booes 
of a year ago, this partnership has blossomed”, Jobs said. 

“With this product we expect to see some additional 
growth within the next six months at Apple”, Jobs said, not¬ 
ing that the iMac was Apple’s first product in several years 
designed to appeal to both the educational and consumer 
markets. The iMac, priced at US$1299 and loaded with 
dozens of nicely designed features, is expected to revive the 
magic of the early Macintosh line among consumers. The 
iMac relies on a Motorola PowerPC processing chip that can 
handle many computer tasks at far faster speeds than the 
most powerful Wintel-based PCs. 

“The iMac will deliver the best and easiest-to-use Internet 
experience, tons of great consumer software, a variety of 
great add-on peripherals, and yes, a high-speed 56K 
modem. We will have lots of iMacs on dealer shelves for the 
US launch on August 15, right on schedule,” Jobs said. 

ELECTRONICS Australia, September 1998 


Designer’s Guide 

to Charging Li-Ion Batteries - 2 

In the first of these articles we looked at the construction and operation of 
modern lithium-ion cells and batteries, and their basic charging requirements. 
Now we can look at the different kinds of charger circuit that can be used, and 
the devices available to implement them. 

by Joe Buxton Battery Chargers Design Engineer, Analog Devices Inc. 

O nce the battery type has been chosen, 
the next major question is which charg¬ 
er topology to use. This question needs 
to be answered regardless of the battery cho¬ 
sen, but the following discussion concen¬ 
trates on Li-Ion. 

The topology choice depends upon the 
application and various system considera¬ 
tions. For example, an in-phone charger 
(placed inside a cellular phone) would prob¬ 
ably need to be a switching regulator buck 
topology, for the efficiency. A linear charger 
in the same application would dissipate too 
much power and generate too much heat. 
Thus, the efficiency of the charger may be 
more important because of the heat generat¬ 
ed rather than the power lost. 

In all chargers, there must be a power 
source. Typically it is an AC/DC adapter, often 
called a ‘wall adapter’, ‘plug pack’ or ‘brick’. 
An exception to this is a charger for use in a 
car. This charger uses the car’s 12V DC. 

For portable computers, the most common 
approach is having an external brick that 
provides a DC input to the computer and an 
internal charger circuit. However the brick 
can be moved inside the computer and com¬ 
bined with the charger. There are advantages 
to each approach. 

The external brick is typically an off-the- 
shelf item that does not require a separate 
design. The internal brick saves the con¬ 
sumer from having to carry additional cords 
and the brick itself. Furthermore, combining 
the brick with the charger can save system 
cost. Essentially, the combination becomes 
an AC/DC supply with 51% output voltage 
regulation and programmable output current. 
In the case of the external brick with an 
internal charger, the ADP3801/02 buck 
topology is ideal. On the other hand, the 
ADP3810 charger was designed primarily 
for AC/DC charger applications. 

Another application is a cellular phone 
charger. Again, there are several different 
topologies: an in-phone charger, a desktop 
charger and a car adapter charger. In the case 

Fig.6: A ‘buck regulator’ type of dual Li-Ion 
with an external P-channel MOSFET. 

of the desktop charger, again the application 
can be divided into an external brick (wall 
adapter) or an internal brick/charger combi¬ 
nation. Also, since the charger sits on a desk¬ 
top, a linear charger such as the ADP3820 
may be the best solution. However, an in¬ 
phone charger would probably require the 
efficiency of a buck solution such as the 

Two key points will determine what type 
of charger to use. First, is the efficiency (due 
to heat generation) important for the applica¬ 
tion? If so, a switching-regulator-based 
charger is the best choice. If not, then a 
lower cost linear charger would be better. 
Second, what will the system topology or 
partition be? If there is a separate AC/DC 
brick, then a DC/DC charger (either linear or 
switching) is appropriate. However, the sys¬ 
tem cost may be lower if the brick function 
is combined with the charger function. In 
this case an off-line charger application is 

battery charger , pairing the ADP3801 device 

the best. All three of these circuit approach¬ 
es are detailed in the following sections. 

A buck charger 

The ADP3801 and ADP3802 are complete 
buck type switching regulator battery charg¬ 
ers/controllers. Fig.6 shows an application 
for a dual Li-Ion battery charger, pairing the 
ADP3801 with an external p-channel MOS¬ 
FET. The ‘BAT PRG MUX’ allows one of 
six final battery voltages to be selected. 
These include one, two or three Li-Ion cells 
(4.2V, 8.4V and 12.6V) and three intermedi¬ 
ate voltages for NiCad or NiMH cells (4.5V, 
9.0V and 13.5V). Also, an input MUX 
allows the part to sequentially charge two 
independent battery packs, which could 
require different voltages. 

When a discharged battery is first placed 
in the charger, the battery voltage is well 
below the final charge voltage, so the current 
sense amplifier controls the charge loop in 


ELECTRONICS Australia, September 1998 

constant current mode. The charge current 
creates a voltage drop across the sense resis¬ 
tor RCS. This voltage drop is buffered and 
amplified by amplifier GM1. Amplifier 
GM2 compares the output of GM1 to an 
external voltage at ISET and servos the 
charger loop to make these voltages equal. 
Thus, the charge current is programmed 
using the ISET input. The output of GM2 
controls the PWM duty cycle and the control 
loop. When the charge current is too high, 
the output of GM2 pulls the COMP node 
lower. It reduces the duty cycle of the PWM, 
decreases the charge current and provides 
negative feedback to complete the charge 
current control loop. 

The output of GM2 is analog ‘ORed’ with 
the output of GM3, the voltage loop amplifi¬ 
er. As the battery voltage approaches its final 
voltage, GM3 comes into balance. As this 
occurs, the charge current decreases, unbal¬ 
ancing GM2, while control of the feedback 
loop naturally changes to GM3. 

To guarantee 50.75% accuracy, a low drift 
internal reference and high accuracy thin 
film resistors are used. Including these com¬ 
ponents on-chip saves the significant cost 
and design effort of adding them externally. 
After the battery has reached its final volt¬ 
age, the current tapers off, as shown in 
Fig.4(a). An internal comparator monitors 
the charge current and — when it drops 
below 80mA — the EOC (end-of-charge) 
output pulls low. This signal can be used by 
the system to show that the battery has com¬ 
pleted charging. 

The LDO section of the chip provides a 
51% regulated output voltage for use 
either as a reference or as a supply 
voltage for external circuitry such as a 
microcontroller. The RESET pin gives 
a power-on reset signal if needed by a 

Finally, pulling the SD pin low 
places the ADP3801 in low current 
shutdown with only the LDO in oper¬ 
ation. This can be very helpful in such 
cases as momentarily stopping charge 
(while a phone call is coming into a 
cellular phone) to prevent switching 
noise from interfering with the RF sig¬ 
nal and to reduce the supply current 
when the charger is not needed. For more 
information on the ADP3801/02, consult the 
data sheet. 

An off-line charger 

The ADP3810 and ADP3811 are ideal for 
use in isolated chargers. Because the output 
stage can directly drive an opto-coupler, 
feedback of the control signal across an iso¬ 
lation barrier is a simple task. Fig.7 shows a 
simplified flyback battery charger. 

The primary side control IC is a standard 
current-mode flyback PWM controller. Its 
wide duty cycle range makes it a good 



0UT ADP3810-8.4 






Fig.7: The simplified schematic for an off-line Li-Ion battery charger of the ‘flyback’ 
type, using an ADP3810 and a PWM3845. 

choice for universal 70-270V AC operation 
and for the additional requirement of 0% to 
100% output current control. This charger 
achieves these ranges while maintaining sta¬ 
ble feedback loops. The PWM frequency is 
set to around 100kHz as a reasonable com¬ 
promise between inductive and capacitive 
component sizes, switching losses and cost. 

The primary PWM-IC circuit derives its 
starting VCC through a 100 kO resistor direct¬ 
ly from the rectified AC input. After start-up a 
conventional bootstrapped sourcing circuit 
from an auxiliary flyback winding would not 
work. The flyback voltage would be reduced 

Figure 9. Linear Battery Charger 

Fig.8: A linear Li-Ion battery charger 
using the ADP3820 controller IC driving 
an external P-channel MOSFET. 

below the minimum VCC level specified for 
the 3845 under a shorted or discharged battery 
condition. Therefore, a voltage doubler circuit 
provides the minimum required VCC for the 
IC across the specified AC voltage range, even 
with a shorted battery. 

While the signai from the ADP3810/3811 
controls the average charge current, the pri¬ 
mary side should have a cycle-by-cycle limit 
of the switching current. This current limit 

has to be designed such that — with a failed 
or malfunctioning secondary circuit or opto- 
coupler or during start-up — the primary 
power circuit components (the FET and 
transformer) won’t be over-stressed. As the 
secondary side VCC rises above 2.7V during 
start-up, the ADP3810/3811 takes over and 
controls the average current. The primary 
side current limit is set by the 1.612 current 
sense resistor RLIM connected between the 
power NMOS transistor and ground. 

The current drive of the ADP3810/381 l’s 
output stage directly connects to the photodi¬ 
ode of an opto-coupler, with no additional 
circuitry. With 5mA of output current, 
the output stage can drive a variety of 
opto-couplers. An MOC8103 is 
shown as an example. The current of 
the photo transistor flows through the 
3.3kO feedback resistor RFB, setting 
the voltage at the 3845’s COMP pin 
and thus controlling the PWM duty 

To minimize cost, a current-mode 
flyback converter topology is 
employed. Only a single diode is need¬ 
ed for rectification (MURD320) and 
no filter inductor is required. A lmF 
(lOOOuF) capacitor filters the trans¬ 
former current, providing an average DC cur¬ 
rent to charge the battery. Resistor RCS sens¬ 
es the average current, which is programmed 
by a DC voltage on the VCS input pin. In this 
case, the charging current has high ripple due 
to the flyback architecture, so a lowpass filter 
on the current sense signal is needed. This fil¬ 
ter has an extra inverted zero to improve the 
phase margin of the loop. The lmF capacitor 
is connected between VOUT and the 0.250 
sense resistor. 

To provide additional decoupling to 
ground, a 220uF capacitor is also connected 
to VOUT. Output ripple voltage is not criti- 

ELECTRONICS Australia, September 1998 


Charging Li-Ion Batteries 

cal, so the output capacitor was selected for 
lowest cost instead of lowest ripple. Most of 
the ripple current is shunted by the parallel 
battery, if connected. 

The VCC source for the ADP3810/3811 
can come from a direct connection to the 
battery as long as the battery voltage 
remains below the specified 16V operating 
range. If the battery voltage is less than 
2.7V (e.g., with a shorted battery or a bat¬ 
tery discharged below its minimum volt¬ 
age), the ADP3810/3811 will be in Under- 
Voltage Lock Out (UVLO) mode and will 
not drive the opto-coupler. In this condition 
the primary PWM circuit will run at its 
designed current limit. 

The VCC of the ADP3810/3811 can be 
boosted using the circuit shown. The 
ADP3810’s VSENSE pin is connected direct¬ 
ly to the battery. This allows direct sensing 
of the battery voltage for the highest accura¬ 
cy. The internal precision trimmed resistor 
divider, the internal low drift reference and 
the internal low offset amplifier all combine 
to provide the 51% guaranteed specification. 

A linear charger 

Fig.8 shows the ADP3820 linear Li-Ion bat¬ 
tery charger controller. Its output directly 
drives the gate of an external P-channel 
MOSFET. As this circuit shows, a linear 
implementation of a battery charger is the 
simplest approach. In addition to the IC and 
the MOSFET, only an external sense resistor 
and input and output capacitors are required. 

The charge current is set by choosing the 
appropriate value of sense resistor, RS. As with 
the ADP380x and the ADP3810, the ADP3820 
includes all the components needed to guaran¬ 
tee a system-level specification of 51% final 
battery voltage. The ADP3820 has an internal 
precision reference, low offset amplifier and 
trimmed thin film resistor divider. 

A universal charger 

Many applications only require the charger 
to charge one specific battery. The form fac¬ 
tor (physical dimensions) of the battery pack 
is usually unique, to prevent the plugging in 
of other battery types. However, some appli¬ 
cations require the charger to handle multi¬ 
ple battery types and chemistries. The design 
for these universal chargers is fairly compli¬ 
cated because the charger must first identify 
the type of battery, program the charge cur¬ 
rent and voltage and choose the proper 
charge termination scheme. Clearly, such a 
charger requires some sort of microcon¬ 
troller intelligence. 

Fig.9 shows a simplified block diagram for 
a universal charger, using a microcontroller 
with the ADP3801. The microcontroller is 
used to monitor the battery voltage and tem¬ 

Fig.9: Simplified block diagram of a universal charger using the ADP3801 and a 

perature via its internal 8-bit ADC and multi¬ 
plexer input. It also keeps track of the overall 
charge time. It may also monitor the ambient 
temperature via a thermistor or analog temp 
sensor. The ADP3801’s LDO (low-dropout 
regulator) makes an ideal supply for the 
microcontroller, and the RESET pin gener¬ 
ates the necessary power-on reset signal. The 
LDO can also be used as a 51% reference. 

When a battery is inserted into the charg¬ 
er, the first step is to identify the type of bat¬ 
tery placed in the charger. The most com¬ 
mon method of doing this is reading the 
value of the in-pack thermistor. Different 
values of thermistors are used to identify if 
the battery is Li-Ion or if it is NiCad/NiMH. 
This thermistor is also used to monitor the 
temperature of the battery. A resistor from 
the ADP3801’s LDO to the battery’s ther¬ 
mistor terminal forms a resistor divider and 
generates a voltage across the thermistor for 
the microcontroller to read. During this time, 
the ADP3801 should be in shutdown, which 
the uC controls via the SD pin. 

When the battery has been identified, the 
microcontroller can do a prequalification 
of the battery to make sure its voltage and 
temperature are within the charging range. 
Assuming that the battery passes, the SD 
pin is taken high and the charging process 
begins. To program the charge voltage and 
charge current, two digital outputs from the 
uC can be used in PWM mode with an RC 
filter on the BAT PRG and ISET pins. A 
connection should also be made between 
the EOC pin of the ADP3801 and a digital 
input on the uC. 

If the battery has been identified as 
NiCad/NiMH, the uC must monitor the volt¬ 
age and temperature to look for -AV/At or 
AT/At criteria for charging. After this point 
has been reached, the charge current can be 
set to trickle charge. A timer function is 
needed to terminate charge if the charge time 
exceeds an upper limit. This is usually a sign 

that the battery is damaged and the normal 
termination methods will not work. 

The ADP3801’s final battery voltage 
should be programmed to a higher voltage 
than the maximum expected charging volt¬ 
age. Doing so prevents interference with the 
NiCad/NiMH charging, yet still provides a 
limited output voltage in case the battery is 
removed. Meanwhile, the ADP3801 main¬ 
tains a tightly regulated charge current. 

If the battery has been identified as a Li-Ion 
battery, the ADP3801 is used to terminate 
charge. The uC should monitor the EOC pin 
for the charge completion signal. In some 
cases, the charge is continued for 30 to 60 
minutes after EOC to top off the battery. If this 
is desired — upon receiving the EOC — the 
timer function should be started. After the 
allotted time, the ADP3801 should be placed 
in shutdown to prevent constant trickle charg¬ 
ing. By using the high accuracy final battery 
voltage limit of the ADP3801, the circuit can 
guarantee safe Li-Ion charging without requir¬ 
ing an expensive reference and amplifier. 


Li-Ion batteries offer exceptional advantages 
in run time, size and weight. These advan¬ 
tages are leading to the widespread use of Li- 
Ion in applications formerly served by 
NiCad and NiMH batteries. Trends show the 
Li-Ion is already the main battery choice for 
portable computers, and the same will be 
true for cellular phones in the near future. As 
production of Li-Ion increases and their 
costs reduce further, additional applications 
will switch to this battery type. 

Li-Ion charging does require high preci¬ 
sion circuitry to guarantee safe and complete 
charging. Analog Devices offers a family of 
parts that satisfy the demands of Li-Ion 
while offering easy-to-use, cost-effective 
circuitry. These parts cover a variety of 
charger topologies, making the job of 
designing a Li-Ion battery charger easy. ❖ 


ELECTRONICS Australia, September 1998 





m u*i] 

Macro Virus Buster 

by Jean-Baptiste Cattley 

U nlike conventional viruses, which 
infect programs, macro viruses 
infect documents, such as Microsoft 
Word .DOC files. These tend to spread 
far more easily, because people tend to 
exchange documents far more readily 
than they exchange programs or disks. 

Another thing going for macro viruses 
is that they are platform-independent; an 
infected document can harm a PC just as 
easily as it can a Mac. This is because all 
macro viruses (including the infamous 
Concept, DMV and FormatC) work along 
the same principles: auto-execute macros 
are inserted into the document, which use 
the built-in scripting language of the doc¬ 
ument’s parent application to copy them¬ 
selves into the application’s default tem¬ 
plate. (i.e. for Word docu¬ 
ments.) From there, they can infect all fur¬ 
ther documents edited. 

As well as merely copying themselves, these 
nefarious little macros can do some very 
unpleasant things, such as deleting files or 
inserting rude messages into all your print jobs. 
Susceptible applications include Microsoft 
Word, version 6 and above, and virtually all of 
the Microsoft Office packages. Theoretically 
any application with a powerful scripting lan¬ 
guage could be affected, but so far, macro 
viruses seem to be limited to Microsoft Office 
products, probably due to their popularity. 

Virus buster 

Although there’s a lot of anti-virus software 
out there, you’ll have a hard time finding any 
that provide decent protection against macro 
viruses. This is where Leprechaun 
Software’s Macro VirusBUSTER comes in. 
MVB is designed only to detect and clean 
macro virus infection in Microsoft Word 
documents, so you wouldn’t want to give up 
your conventional virus checker right away. 

Unfortunately, Leprechaun software reports 
compatibility problems with conventional 
antivirus software, so you may have to decide 
which kind of virus you fear the most. I found 
no problems running MVB in conjunction 
with VET Anti Virus, for example, but other 
software may not be quite so forgiving. 

As well as giving you the option to manu- 

Computer viruses have gained 
much attention in the past, and a 
healthy proportion of people now 
regularly run virus checkers on 
any new software they obtain. A 
fairly new addition to the viral 
'gene pool’ is the macro virus, 
which can wreak just as much 
havoc as an ordinary file or boot 
sector virus, but very few people 
bother to check for them. Here’s 
where Leprechaun’s new product 

comes in... 

ally scan directories for infected files, MVB 
installs a VxD into the operating system that 
checks all documents as they are accessed, 
guaranteeing that all documents are scanned 
before they can do any harm. 


The software is supplied on two floppies, 
one for use on Windows 3.lx systems, and 
the other for Win95. There’s also a Windows 
NT version available, but this wasn’t sup¬ 
plied in the package I received. 

I installed the Windows 95 version, which 
used InstallShield to set everything up, and 
as a result I was later able to uninstall it 
cleanly using the ‘Add/remove programs’ 
option in the control panel. Once installed, a 
blue ‘M’ icon in the system tray indicates 
that MVB is running, and that all office doc¬ 
uments will be checked as they are opened. 

Every time you open, close or save a Word 
document, MVB flashes a green tick mark in 
the top right hand comer of your screen, to 
indicate that it has checked the document and 
found no macro viruses. This is a little dis¬ 
concerting at first, as it writes directly to the 
screen instead of using a conventional win¬ 
dow or dialog box, but you soon get used to it. 

Manual scanning is quite straightforward 
— a button on the MVB main window brings 

up a directory requester, allowing you to 
select a directory to scan. Interestingly, if 
you want to scan a single file, you have to 
find it in Explorer and drag it on manual¬ 
ly; surely a standard file requester instead 
of a directory requester would have been 
more appropriate? Once manual scanning 
has finished, MVB proclaims in a broad 
Australian accent “The scan was complet¬ 
ed with no problem”. This is fun at first, 
but after the fifth repetition, it wears some¬ 
what... Luckily, there is a way to turn it off 
in the setup panel. 

Perhaps the most interesting aspect of 
Macro VirusBUSTER is that along with 
normal vims signature scanning, (as used 
by conventional vims checkers) it uses a 
process called Heuristic Scanning. In this 
mode, MVB looks at the actual code con¬ 
tained within any Word macros, and tries 
to determine whether that code could do 
anything harmful; in this way, it can theoret¬ 
ically detect previously unknown macro 
viruses. For this reason, Leprechaun 
Software have splashed ‘No upgrades need¬ 
ed!’ across the box, but I’m sure that a new 
version of Office will fix that soon enough... 

In actual use, Macro VimsBUSTER is trans¬ 
parent, fast and inconspicuous. I’ve had it run¬ 
ning for the best part of a month, and haven’t 
come across any problems. The only real gripe 
I have is the potential compatibility problems 
with conventional vims checkers; a little more 
information in the manual on this point would 
have been useful, but I certainly haven’t struck 
any problems — and the knowledge that the 
next piece of email I receive won’t eat my hard 
drive is certainly reassuring. ♦> 

Macro VirusBUSTER 

Macro Virus protection for Microsoft Word 

: Fast, transparent operation, 
minimal setup. 

: Possible problems with other 
anti-virus software. 

:Leprechaun Software Australia, 
PO Box 826, Capalaba QLD 4157. Phone 
(07) 3823 1300; fax (07) 3823 1233, email; website at 

ELECTRONICS Australia, September 1998 



News & New Products 

USB-based instruments 

National Instruments claims to be the first to 
introduce instruments that connect to 
Windows 95 PCs via the Universal Serial 
Bus (USB). The family of instruments 
includes a two channel, deep memory digital 
oscilloscope (NI 5102); a 5-1/2 digit multi¬ 
meter (NI4060) and a high-precision temper¬ 
ature and voltage measurement instrument 
(NI 4350). The instruments are compatible 
with industry-standard software packages 
including LabVIEW, LabWindows/CVI, 
Visual C/C++, and Visual Basic. 

CD Writer drive from Kodak 

Kodak’s new Digital Science 2801 IDE CD 
Writer allows PC users to take advantage of 
the low cost and high capacity that CD-R 
media provides, along with the very latest in 
CD-R recording software technology. 

The 2801 IDE CD Writer has several new 
features over its predecessor, the 26001DE. 
The 2801 IDE is an 8X read unit, has 
improved software functionality, help fea¬ 
tures, user interface and audio writing capa¬ 
bilities. The new Writer also has an 
improved installation manual to ensure a 
trouble-free installation process. 

The 2801 IDE CD Writer is an internal 
ATAPI-IDE unit that is 2X speed write and 
8X speed read. It is aimed at both mainstream 
and high-performance personal computer 
users and is ideal for desktop/web publish¬ 
ing, software developers, small office/home 
office, business professionals and home 
users. It simply plugs into the IDE port avail¬ 
able inside most IBM compatible PCs. 

The software provided is CeQuadraf s lat¬ 
est offering, CeQuadrat ToGo! 4.5 along 
with CeQuadrat Packet CD. The Packet CD 
software allows users who want to share and 
store their information to treat their CD-R 

All of the USB-based instruments are 
compatible with Windows 95 (OSR 2.1) and 
Windows 98. Each instrument includes 
instrument drivers and the appropriate acces¬ 
sories, cables, and probes. 

The NI 5102 digital oscilloscope’s features 
include 20MS/s real-time maximum sample 
rate; lGS/s random interleaved sampling 
(RIS); 15MHz input bandwidth; 663,000 
sample record length; two input channels, 
one analog trigger; 50mV - 5000V input 
capability; and 8-bit vertical resolution. 

The NI 4060 digital multimeter’s features 
include 5-1/2 digit DMM with AC/DC cou¬ 
pling; true-RMS AC measurements, 20Hz - 
25kHz; DC and AC input ranges of 20mV - 
250V; and resistance measurements of 
200C2 to 20M£1 

For more information circle 161 on the 
reader service card or contact National 
Instruments Australia, PO Box 466, 
Ringwood 3134. 

Fast Ethernet link tester 

The LanMaster Model 20 Link Tester pro¬ 
vides LAN installers and technicians a tool 
to quickly test active Links in Fast Ethernet 

disc just like any floppy disk or hard disk 
drive by using the ‘File Save’ feature of 
their existing software, or simply dragging 
and dropping their files. 

The 2801 IDE CD Writer measures 147 x 
211 x 41 mm and has the same form factor as 
a half-height 5-1/4” floppy drive. It’s avail¬ 
able for around $617 through a wide net¬ 
work — including retailers, camera dealers, 
catalogues and traditional computer dealers. 

For more information circle 160 on the 
reader service card or contact Kodak Digital 
& Applied Imaging, 173 Elizabeth Street, 
Coburg 3058. 

(lOObaseTX) and Standard Ethernet 
(lObaseT) networks. In just three seconds, 
the LanMaster 20 verifies Link operation, 
identifies Fast Ethernet capabilities of 
installed equipment and displays reported 
fault status. The Model 20 also retails for 
only $395, which is claimed to make it the 
most affordable Fast Ethernet test instrument 
available on the market. 

The Fast Ethernet (IEEE 802.3u) standard 
defines several new operating modes and 
technical capabilities for LAN products. 
Auto-sensing, Auto-negotiation and Full 
Duplex operation are some of the new fea¬ 
tures that dramatically increase network per¬ 
formance and maintainability. These 
enhanced modes and capabilities are only 
optional requirements to the IEEE 802.3u 
standard and installed equipment can have 
very different levels of Fast Ethernet sup¬ 
port. These features can also be configured 
during installation or operation further 
increasing the difficulty of maintaining or 
upgrading a network. The LanMaster 20 
Link Tester provides important configura¬ 
tion and fault information by detecting and 
decoding Link signals transmitted by the far- 
end equipment. The decoded configuration 
and fault information is displayed to the user 
through eight backlit display cells. 

The LanMaster 20 reduces Move, Add 
and Change (MAC) problems by quickly 
verifying connectivity and wiring polarity 
for a new or modified network Link. It sim- 


ELECTRONICS Australia, Setember 1998 


plifies troubleshooting by confirming physi¬ 
cal layer operation for an active Link and 
improves network management by providing 
equipment configuration information needed 
to optimize system performance. 

The handheld unit is light (11 Og) and small 
(175 x 38mm), making it a natural addition to 
a Network Maintained tool kit. The unit is 
easy to operate with all tests performed by a 
single press of a button. One 9V battery pow¬ 
ers the product and an RJ-45 coupler is 
included for connecting to a patch cable. 

For more information circle 162 on the 
reader service card or contact Jamsam Pty 
Ltd, Suite 202 James Hardie House, 65-69 
York Street, Sydney 2000. 

Aussie microPLC 
for OEM users 

Just released in the all-Aussie SPLat range of 
microcontrollers is a model designed specifi¬ 
cally for OEM users. The easily programmed 
and operated microPLC offers manufacturers a 
cost effective alternative to fully custom-built 
controllers and saves on engineering costs. 

The MMI88 is based on a general purpose 
SPLat controller — for timing, counting, 
sequencing and digital control functions. It 
features an inbuilt operator interface that is 
specially tailored, with a polyester graphics 
overlay, for the ‘look and feel’ needed in the 
end application. 

Designed by Microconsultants in Victoria, 
the MMI88 is designed for machinery man¬ 
ufactured in small to medium volumes. The 
system shortens the time needed to develop a 
product and get it into the market place. 

With a combination of eight inputs, eight 
outputs, eight timers and a high speed 
counter, plus five pushbutton switches, 
seven LEDs, a beeper and two configuation 
jumpers, the MMI88 performs simple to 


| Ready 

• Over Temp 

* Cycle Done 
"check 0« 

f Sensor Fell 
(§ Bin Empty 

^ MMI88 @ 

Sample graphical CT) 



Your graphics for >v>*r Q 

SPLtf «"**** 

complex control functions. 

Microconsultants’ OEM support team also 
offers a programming service to get manu¬ 
facturers going even faster. 

For more information circle 163 on the 
reader service card or contact 
Microconsultants, 2/12 Peninsula 
Boulevard, Seaford 3198. 

Recordable DVD-R 
and DVD-RAM media 

TDK has announced DVD-R and DVD- 
RAM recordable and re-recordable discs. 
Although not available in Australian yet, 
TDK (Australia) will meet market require¬ 
ments as they develop. 

Offering storage capacity up to 5.2GB 
(DVD-RAM double sided), the media 
employ the latest in optical storage develop¬ 
ment technology. Compatible with current 
DVD-R recordable drives, TDK’s DVD-R 
uses a metal stablised cyanine dye as the 
recording layer and gold as the highly reflec¬ 
tive layer. These integral layers are bound 
together by a proprietary UV curing resin 
bonding process that also aids in protecting 
the disc. 

TDK’s DVD-RAMs are a rewritable DVD 
media offering storage capacity of 2.6GB 
(single sided) and 5.2GB (double sided). 
Designed to be re-writable for up to 50,000 
times, the discs employ a Ge amorphous 
alloy in the phase change layers (recording 
layers) and aluminium for the reflective lay¬ 
ers. The four-layer construction is secured in 
place by a proprietary UV curing resin bond¬ 
ing process. 

For more information circle 164 on the 
reader service card or contact TDK 
Australia, 22 Lambs Road, Artarmon 2064. 

Q International 



Hy-Q manufacture 
and stock an extensive 
range of Quartz 
Crystals, Filters and 
Oscillators including 

We also supply a full 
range of high quality Ceramic devices at competitive 
prices. Hy-Q specialises in quality, service and delivery. 

Telephone (03) 9562 8222 
Facsimile (03) 9562 9009 


EDI UPl-series 60 amp bridges 
assure the reliability of your 
equipment with these features: 

1000 amp surge handling capacity 
Reverse voltages from 50 to 1000 volts 
Available in fast recovery versions 
Rapid assembly, through-hole mounting 
Choose quick connect or wire leads 

Don't delay, call or fax today for more 
details and for catalogues on three- 
phase bridges, hv diodes and assemblies. 

Unit 2, 6-10 Maria Street Laverton North, Vic 3026 

Tel: (03) 9369 8802 Fax: (03) 9369 8006 

ELECTRONICS Australia, September 1998 




News & New Products 

Dual platform A3 
Bubble Jet printer 

Canon has released the new BJC-4650, 
claimed as the industry’s first A3 Bubble Jet 
printer for PC or Mac to offer users full 
colour scanning (optional) and PhotoRealism 
printing capabilities from a desktop printer. 

The BJC-4650 is the only printer in its 
class that is easily converted from a printer 
into a colour scanner. The optional scanner 
cartridge is substituted for the ink cartridge, 
turning the printer into a colour scanner 
capable of scanning resolutions up to 
360dpi. This facility can be used to scan 
images up to A3 in size, into a Windows 95 
compatible computer. 

The BJC-4650 also achieves near silver 
halide photographic output using Canon’s 
unique PhotoRealism and Drop 
Modulation Technology. 

By replacing the colour cartridge with the 
black ink cartridge, the BJC-4650 produces 
high speed, sharp, true black text documents. 
Users can accomplish speeds of up to 4.5 A4 
pages per minute in high-speed mode, and 
with the text smoothing function documents 
are near laser quality. 

The BJC-4650 has an RRP of $599 and 
comes complete with a four-colour ink car¬ 
tridge, a photo ink cartridge, five sheets of 
glossy photo paper and a cartridge storage 
container. Also available is the optional 
scanner cartridge priced at $149 and a black 
ink cartridge for $58. 

For more information circle 165 on the read¬ 
er service card or contact Canon Australia, 1 
Thomas Holt Drive, North Ryde 2113. 

Keyboard and mouse adaptor 

PI Engineering’s Keyboard and Mouse 
Adapter is an active device that allows the 
simultaneous use of both a full-size keyboard 
and normal mouse on a notebook computer. 

The adapter works with all notebooks that 
feature a PS/2 keyboard/mouse port. It 
requires no external power supply, drawing 
power directly from the notebook port. Driver 
software is included for Windows 95 and 
Windows 98. No additional IRQ’s or com 
ports are required. 

Suggested retail price is A$129 including 
tax, with a 12-month warranty. 

For more information circle 167 on the 
reader service card or contact BJE Enterprises, 
124 Rowe Street, Eastwood 2122. 

Rugged multi-axis joystick 

Developed for use in those applications 
where lever strength and handle functionali¬ 
ty are paramount — like virtual reality sys¬ 
tems — the Penny & Giles JC600 is a large, 
robust, multi-axis joystick that can be easily 
tailored to your application. 

Designed for use with electronic controllers, 
conductive plastic tracks inside the JC600 
generate analog and switched reference sig¬ 
nals proportional to the distance and direction 
over which the handle is moved. A centre tap 
on the analog track provides an accurate volt¬ 
age reference for the centre position or a zero 
point for a bipolar supply voltage. 

The JC600 range of ergonomic handles fea¬ 
ture potentiometers, for three and four axes of 
control, switches, membrane keypads or LED 
displays. Deadman switches or a centre lock 
option can be specified to improve the integri¬ 
ty of a control system. Installation time has 
been reduced through the use of standard 
electronic connectors. System cost can be fur¬ 
ther reduced by replacing the JC600 interface 
board with a CANBUS or PWM controller. 

With an expected life in excess of five 
million cycles and designed to meet a lkV 
voltage test, the JC600 is currently specified 
by manufacturers of access platforms, agri¬ 
cultural, construction, mining and material 
handling equipment. 

For more information circle 168 on the 
reader service card or contact Control 
Devices Australia, Level 1, 150 William 
Street, East Sydney 2011. ♦> 

Pentium II based 
Little Board SBC 

Aaeon Technology has released the PCM-7890 
Pentium II Little Board single board computer, 
with on-board CRT/LCD controller and the new 
DiskOnChip Flash Disk. The on-board 100BaseTX 
Fast Ethernet interface, TV output and Sound 
Blaster compatible audio opens up worlds of pos¬ 
sible applications for kiosks, gaming systems, POS 
systems, medical and educational products. 

The ultra compact board packs all the functions of an embedded PC on a single board, but fits 
in the space of a 5-1/4” floppy drive. The on-board C&T 69000 is a high performance LCD/CRT 
Windows accelerator incorporated with 2MB SDRAM for graphics/video frame buffer. It sup¬ 
ports a wide range of flat panel displays, including 36-bit TFT LCD displays allowing simultar 
neous viewing of LCD/CRT and TV display. 

The built-in DiskOnChip supports system boot-up and memory storage up to 72MB. The 
fast Ethernet provides a tenfold increase in network capability; it is fully compatible with 
lOMb/s network facilities. High quality sound requirements are also provided for, with an on¬ 
board PCI bus ES 1371 sound controller which is compatible with Sound Blaster, Sound 
Blaster Pro and Windows Sound System. 

Also included are four high speed serial ports (three RS-232, one RS-232/422/485), one 
multi-mode (ECP/EPP/SPP) parallel port, a floppy drive controller, an Ultra DMA/33 
enhanced IDE controller and a keyboard/PS/2 mouse interface. 

For more information circle 166 on the reader service card or contact Amtex Electronics, 2 A 
Angas Street, Meadowbank 2114. 


ELECTRONICS Australia, September 1998 

by Graham Cattley 

B uilding your own pc really 

isn’t that difficult you know, especial¬ 
ly after looking through Jeff Moe’s site 
at He takes 
you step by step through deciding what you 
want, buying the bits, putting it all together 
and so on. Just about all the pages warn you 
that “...the info on this site is really old”, 
but it covers 686’s at 150MHz, so it isn’t 
that out of date. Besides, most of the info 
here is relevant, no matter what speed CPU 
you’re running. 

He also has lots of useful links, and a sep¬ 
arate updates page for submitted material that 
hasn’t had time to intergrate into the site. 

Work left to do on these pages 


Mfcrnai Dffcbiffc* £*<«*« m im 

J£i' —— 

All up, a useful, informative site that will 
appeal to anyone contemplating building a 
computer from scratch, or simply upgrading. 


covers a fair amount of ground, with sections 
on the operation of faxes and photocopiers 
(both of which are very good), cable 
descrambling, and several simple projects to 
build. It’s worth a look. 

port? Do you know what LZW stands for? 
and should DR.BOND be using FOSSIL on 
the LAWN? Don’t know what I’m talking 
about? Go to 
/-ikind/babel.html, where Irving Kind main¬ 
tains the biggest acronym and abbreviation 
index that I’ve ever seen. It comes as a huge 
single page, so you’ll have to wait for all of it 
to load in before you start searching — or you 
can FTP the zipped text version from Irving updates it three 
times a year, and so the whole thing is quite 
compehensive and up to date. (Although I 
couldn’t find LRF, which stands for Little 
Rubber Feet...) 

glish/nano/arte.html is very good — 
Cherry Blossoms in a Clear Stream is quite 
beautiful, as are the Gold Moon and Desert 
Passion photos. They’re photomicrographs 
of course, but taken out of context and suit¬ 
ably coloured they take on a whole new 
meaning. It’s all very Japanese, and well 
worth the effort of typing in the long URL. 

CONSIDER THIS the next time you are 
online: one white pixel uses up 34,475,867,928 
electrons per second. An average 14” screen 
uses 18,237,881,012,857,875,948,329,134,987 
electrons per second. These electrons are 
destroyed and cannot be used again. See 
what’s being done to save the electron at 
http ://www.and j s 2 

CAR AUDIO is always a hot subject, and 
the site (at, of course) 
can give you heaps of stuff on the subject, 
mainly via their FAQ (yes, 
from the Usenet newsgroup). 

Their White Pages list the sites of people 
around the world where you can see other 
installations and even email other car audio 
enthusiasts. There are details of upcoming 
‘sound-off competitions (mostly in the US), 
a colourful report of the new car audio prod¬ 
ucts at the recent ICES, and links to car 
audio retailers online. So if you see your car 
as merely a speaker box on wheels, this site 
should be of great interest. 

your VCR, then why not pay a visit to, 

where Philip Kuhn offers a listing of Q&As 
on just about every aspect of owning and 
operating a VCR. An interesting image 
map indexing system takes you quickly and 
easily to the relevant section, with useful 
hints and tips on the section of VCR that 
you clicked on. 

And if you are still one of the many suf¬ 
fering from a blinking 12:00 on your VCR, 
check out 
/vcr.html, which covers the time setting 
procedures for a multitude of popular 
domestic VCRs. ❖ 

ELECTRONICS Australia, September 1998 


EA Directory of Suppliers 

Which of our many advertisers are most likely to be able to sell you that special component, instrument, 
kit or tool? It’s not always easy to decide, because they can’t advertise all of their product lines each 
month. Also, some are wholesalers and don’t sell to the public. The table below is published as a spe¬ 
cial service to EA readers, as a guide to the main products sold by our retail advertisers. For address 
information see the advertisements in this or other recent issues. 


State A 



D E 







• • 



Dick Smith Electronics 




• • 



Emona Instruments 



Jaycar Electronics 

Eastern • 



• • 



Oatley Electronics 

Eastern • 

• • 




RCS Radio 



Scientific Devices 






A Kits and modules 


1C chips and semiconductors 

B Tools 


Test and measuring instruments 

C PC boards and supplies 


Reference books 

Note that the above list is based on our understanding of the products sold by the firms concerned. 

If there 

are any errors or omissions, please let us know. 

Electronics Australia Reader Services 

SUBSCRIPTIONS: All subscription enquiries should be directed to: Subscriptions Department, Federal 
Publishing Company, P.0. Box 199, Alexandria 2015; phone (02) 9353 9992. 

BACK ISSUES: Available only until stocks are exhausted. Price A$7.50 which includes postage within 

PHOTOCOPIES: When back issues are exhausted, photocopies of articles can be supplied. Price $7.50 per 
project or $15 where a project spreads over several issues. 

PCB PATTERNS: High contrast, actual size transparencies for PCBs and front panels are available. Price is 
$5 for boards up to, $10 for larger boards. Please specify negatives or positives. 

PROJECT QUERIES: Advice on projects is limited to postal correspondence only and to projects less 
than five years old. Price $7.50. Please note that we cannot undertake special research or advise on pro¬ 
ject modifications. Members of our technical staff are not available to discuss technical prob¬ 
lems by telephone. 

OTHER QUERIES: Technical queries outside the scope of ‘Replies by Post’, or submitted without fee, may 
be answered in the Information Centre’ pages at the discretion of the Editor. 

READER SERVICES BULLETIN BOARD: (02) 9353 0627; ANSI, 24 hour access; any rate to 28.8kb/s. 
PAYMENT: Must be negotiable in Australia and payable to Electronics Australia. Send cheque, money order 
or credit card number (American Express, Bankcard, Mastercard or Visa card), name and address (see form). 
ADDRESS: Send all correspondence to: Reader Services Co-Ordinator, Electronics Australia, P.O. Box 199, 
Alexandria NSW 2015; phone (02) 9353 0620. (E-mail to 





Back issues: 


Amount: A$. 

Signature:.(Unsigned orders cannot be accepted.) 

Method of Payment: (Please circle correct method.) Credit card / Cheque / Money order. 
Credit cards accepted: 

Mastercard, American Express, Visa Bankcard (please circle applicable card). 

Expiry date:. 


Allthings Sales & Services.43 

Altronics .64-66 

Bainbridge Marine.33 

Bendigo College of TAFE.9 

Campad Electronics .83 

Central Park Electronics .83 


Control Devices.85 


Dick Smith Electronics .38-41,IFC.OBC 

EA subscriptions offer.82 

Elenex .60 

Evatco .71 

Fastron Australia.33 

Griffith University .9 

Harbuch Electronics .81 

Hewlett-Packard Australia.13 

Hy-Q International.95 

Instant PCBs.83 

Jands Electronics .73 

Jaycar Electronics .52-55 

JED Microprocessors .51 

McLean Automation .81 

Microgram Computers .23 

Netcraft .63 

Oatley Electronics .IBC 

Obiat .87 

Procon Technology.61 

Result Electronics.35 

Questronix .22 

Scan Audio.22 

STA .81 

Taig Machinery.83 

Tandy Electronics.29 

VAF Research.12 

Valve Electronics.73 

Westek Industrial Products.95 

This index is provided as an additional service. The 
publisher does not assume any liability for errors or 

Notes & Errata 

Forum column (July 1998): The telephone num¬ 
ber given for Melbourne firm Bio Electronics is 
wrong; it should be (03) 9370 6729. 

240V Variable Frequency Drive (July 1998): In 
the schematic diagram on page 57, rectifier bridge 
B1 should be rotated clockwise by 90°; also zener 
diode Z2 is reversed. The PCB overlay is correct. 
Motorcycle Intercom (July 1998): Capacitor C2 
should be a lOuF electrolytic, not luF as shown in 
the schematic. The parts list and overlay diagram 
are correct. 

$10 Wonders (June 1998): In the stripboard over¬ 
lay on page 67, the LED anode should connect to 
J6, to connect to R3. Also the flying lead should 
connect to track H11, not F12 as shown. Thanks to 
Ted Kilminster for advising of these errors. ♦> 


ELECTRONICS Australia, September 1998 

Very bright ( 650 nM ) pointer, supplied 
with 4 extra lens caps that 
produce symbols; CUPID 
LADY. $29 

Same quality module that 
is used in the above 
laser pointer: $24 

Data logger/sampler plugs into your Pc’s 
parallel /printer port & takes samples over 
a 0-2V or 0-20V range. Samples can be 
taken at intervals from one per hour down 
to one per IOOuS. Useful, for example, to 
monitor battery charging. It can also be 
used as a basic low frequency (to about 
5KHz) oscilloscope! Our kit includes all 
onboard components, A _ 

PCB, Db25 $40 


software on 
a 3.5" disk: 


PC Data Acquisition Unit 
Use the parallel port of your PC as a real 
world interface. It enables your PC to both 
monitor & control external events and 
devices. The world is a mixed analog & 
digital world. VMth the appropriate sensors 
the PC can monitor physical variables 
such as pressure, temperature, light 
intensity, weight, switch state, movement, 
relays, etc, process the information and 
then use the result to control physical 
devices such as motors, sirens, other 
relays, servo motors (up to 11) & two 
stepper motors :$200 


12VDC - 240AC INVERTER Features include modified square wave output, Auto 
start with load sensing, Uses six power MOSFETS 
with minimal heatsinking required. 200- 
600VA. dependant on transformer size. 

To save money you can use an rewind 
your own transformer. Basic kit includes 
pcb & all on-board components + 4 60A 
MOSFETS. $35 Requires 240V to 8-0-8 V 
transformer. Low profile case + Australian 
made300VA. (cont.) trans-former for approx. $100. 


This kit could be used as an answering machine at your front door or as a personal 
reminder device and is very easy to assemble 
Produces very good quality sound at 25 
sec (better than most expensive units), 

Uses Large Scale Integration 
chip with memory etc. all 
built in. Kit includes 
PCB, all on-board 
components, electret 
microphone, switches & 
small surplus speaker. $ 19 




soon to be ( 


Your own mini Tv broadcast static 
Send video from VCR's or $i5 

cameras to TVs in your ^ 

home. Inc. Metal case 
telescopic antenna & leads: 

12V operation, tunable (G01) 

$20 or $15 with camera purchase 

MOTORS 30 oz./in. TORQUE, 2.5 DEG. 

MOTOR KIT: can drive larger motors with 
optoisolation. Inc. software and notes: $50 
or $65 with two used 2.5 deg.jriotorsji 

DRIVER KIT Kit inc. a large 
used 2.5 deg. (144 step/ 
rev) motor & uses SAA- 
1042A 1C. Controls inc. ext. clock, 
on-board clock logic CWor CCWrotation, 
half or full step, enable/disable, clock 
speedl motor: $25 or 2 motors:$35 


In a small black metal 
case. Built in switch & 
microphone. Specs.: 

88 to 108-MHz (adj.), 
with a wire ant. bat. life 60^ 
hrs, Range 50M:(G14) $39 
(Std. watch battery LR44, inc.) 


High quality mirrors 160x22x2.5mm. 
with some minor blemishes Ideal for laser 
& other optical projects $5 

Brand new 240V 
30cm enclosed 
computer monitor 
+ video conversion 
kit. Gives better 
resolution than TV! 

Limited good qty. 



Ref: SC Jul 95. Allows two trains to run on 
one track, without hitting each other due 
to speed difference. VMien a train breaks 
an IR beam it switches off power to a 
portion of track, until the other train 
catches up & breaks another beam at 
another location. It uses a relay to switch 
sections of track. Main PCB: 96 x 66mm, 
IR Sensing PCB's: 59 x 14mm: (K58) $28 

MKIII. Similar kit as per SC. May 96, The 
display changes every 5 - 60 secs, & is 
manually adjustable. For each displays 
there are 8 speeds for each of 3 motors, 
one motors can be reversed in direction, & 
one motors can stopped. There’s 
countless interesting displays which vary 
from single to multiple flowers, collapsing 
circles, rotating single and multiple 
ellipses, stars, etc. Now with no more 
mirror and motor alignment hassleswith 
motor mounting on the PCB and mirrors 
now align with “Allen Key”. Kit includes 
PCB, all on board components, three 
small DC motors, mirrors, precision 
adjustable mirror mounts :(K83) 


3.3 A@ 14V PELTIER: $27, 6A 
@15VPeltier: $35, both are approx. 
40X40X4mm, can be temperature con¬ 
trolled by reducing supply voltage 
/current, will even work from a 1.5V 
battery!! V\te supply Peltier Effect device, 
data sheet, diagram & circuit for a small 
fridge / heater.. Other requirements; In¬ 
sulated box, 2 large heatsinks, & a small 
aluminium block, this device is used in the 
common 15Lrcar 
fridge. Peltier effect 
Device:(G02) 12 V, 

DC Fan:(G11) 


PO Box 89 Oatlev NSW 2223 

Ph (02) 9584 3563 Fax 9584 3561 
orders by e-mail: 
major cards with ph. & fax orders, 
Post & Pack typically $6 




Great for cars, radios mobile phones, fog 
lights etc. 4 colours, 2 guages of wire, 
Spade connectors, fuse holders, fuses. 
17+ mtrs. of wire. Limited offer! 11 just $1 

Fresh stock of NEWstandard battery $22 

Can be programmed as 
a spare for your current 
remote or to replace up 
to 4 other units and 
combine into 1:(TX1) $39 

Stamp sized Xtal locked 433.9MHz 
superhetrodyne receiver module $25 
Small matching transmitter kit: $12 

00 *- 



0|» o D 

Three spring units. Dim.: 425 x 110 x 
33mm. Input Z=190 ohms, output Z=2.6 
k ohms, recommended AC drivej, 

6.5 mA. A circuit diagram 
of a stereo pre¬ 
amp tested 

using this a o 

unit:$40(A10) s>4U 

The best "value for money" CCD camera 
on the market! 0.1 lux, High IR response & 
high res. Performs better thgn_ many 
cheaper models. WITH 
Pinhole (60deg.), 

;78deg.; 92 deg.; 

120 deg.; $89 or 150 deg: $99 

3V - 8v DC motors with feedback winding 
for speed sensing ect. 40mm diameter 

Lm338 adjustable ( T03 package ) 5A 
voltage regulator with int ernal ov erload 
protection, + applicatioj 
notes for a variable 
1.2V- 33V 5-20A 
power supply 
Half price at 
or 4 for $16 



"* NEW *" NEW *" NEW "* 
RECEIVER Applications include data 
transmitter, powerful Passive infrared de¬ 
tector, IR invisible fence / gate & doorway 
monitor. Range: with 5 IR LEDs (can drive 
up to 50 LEDs) passive mode 10m (5 
LEDs), active mode 40m (5 LEDs). Range 
can be boosted with a cheap torch re¬ 
flector. The kit has active high & active low 
outputs for relays etc Simple to construct 
PCB can be cut into two for active mode or 
for data transmission. Kit inc. PCB, all on¬ 
board components, 5 IR LEDs + salvaged 
new plastic case All for $28 

Cf300, LOWNOISE (NF=1.4 @800 Mhz) 
V\fould make extremely low 
noise RF amp (Gps 23db). 

WAth brief info. $3 Ea or 5 for $13 

$2 " YES " $2 

SHEET:$ 2 (Rm2). This unit [fit neatly 
with our camera in our 50; J ^ 

50x50mm case + swivel 
mount strong adjustable 
universal bracket: $4 
Bracket only :$ 1.50 


New assembly. 45 x 108 x 200mm. 120 / 
230V AC input. DC outputs are +5V@ 
6A.+ 12V@ 1A,-12V@1A,-5V@1AJ3ata 
Inc.RU approval. Mail 
input. Be Quick: 

or 4 for $36 

This device contains an IR 
receiver diode, an amplifier 
tuned to 38KHz, a bandpass 
filter, an AGC section & de¬ 
tector circuit. $2 Ea or 10 for $15 

High Power High Frequency 
EHT generator that will give an 
exciting plasma discharge with 
a std light bulb or make Jacobs 
Ladder or Laden Jar & other EHT 
applications. Can be converted to 
a DC. Supply with a HV diode. 

Inc. EHT transformer + PCB 
all on-board parts & 1KV. fast 
Diode + application notes. Req 
12V @ 0.5-2A. Special price $29. 
16KV. Diode $1.50 

lline x 16char.:$16 p 
2 line x 16 char, with 
LED back-light:$24 

40mW/785nM For scientific, 
medical and industrial 
applications: $65 
35 mW/650 nM: $90 


This kit has two PCB's + current limit 
resistors + 60 LED's to make a very bright 
brake light etc. 600mm long: $15 



European made, new, "slim line" case high 
frequency (HF) electronic ballasts. Flicker 
free starting, long tube life, high efficiency, 
visual flicker during operation. Reduced 
radio frequency interference. Similar 
design to one published in the Oct. 94 
Silicon Chip, although these are much 
more complex. Dimming requires external 
100K pot or a 0-10V DC source. V^eJiave a 
limited stock 1 x 36W 
tube, 28 x 4 x 
3 cm: (G09F) 
iust $18 

Reader Info No 34 

Credit card remote 

One instead of four! 

Integrates up to four different controls into one 
ultra-slim credit card size remote. 
Pre-programmed and easy 
to use. 


G 1220 

37 95 

Universal remote control 
jog shuttle 

Replace up to 8 remotes with this easy-to-use 
master controller. Pre-programmed and learning. 
LCD screen,Teletext function and 
jog/shuttle control. G 1212 

FOX600 Universal remote control 

Control six devices from one remote! This easy-to-use 
pre-programmed unit is ideal for TVs, VCRs, satellite 
receivers, cable boxes and CD players. 

Includes teletext, g 1225 



Commander remote control 

Reduce remote clutter with this 8-in-1,full LCD 
touch screen remote with macro functions. Home 
theatre/surround sound ready. 

G 1210 


Help is Just A Toll-Free Phone Call Away! 

The most user-friendly Universal Remote Controls Available. If you ever have any questions or need 
help of any kind to program your One for All Remote Control, Just call 1-800-064-472 (Toll-free) 

I for 3 universal remote control 

Great new design! 

Throw out your old remote controls! This 
pre-programmed unit replaces up to 3 

remotes. Now access 
Jp J|dL|| y° urTV ’ VCR and cable 
from the one remote. 

G 1271 

I for 4 universal remote control 

Backlit, and replaces up to 4 remotes. 
Pre-programmed for TVs,VCRs, 
cable boxes and CD players. 

G 1261 



direct; Jink 



PHONE: 1300 366 644 (Local Call Charge) FAX: (02) 9395 1155 

MAIL: DICK SMITH ELECTRONICS, Direct Link Reply Paid 160. 

PO Box 321. North Ryde NSW 21 13 (No Sump Required) 

Please add postage (up to Skg) to your order, as follows: 

• $4.00 Up To $50 • $7.50 $51 Up To $100 • $9.00 $101 Up To $500 • $11.00 over $500 
(quote available for air/road freight or if over 5kg) email: (enquiries only) 

•Major Credit Cards Accepted. • Gift Vouchers Available 

I for 5 universal remote control 

Easy-to-use and conveniently 
replaces up to 5 remotes 
including TVs, VCRs, cable 
boxes, CD players, 
audio equipment. g 1250 

I for 6 universal remote control 

Pre-programmed and easy set up. Controls TVs,VCRs, 
cable boxes, audio appliances 
and Teletext. Replaces up 
to 6 remotes. G 1240 

Universal remote control 
A/V producer I for 8 

Access up to 8 devices from one remote! 
Pre-programmed unit includes backlit keypad, 
LCD and home theatre mode 


G 1280 

For further information, orders or the 
location of your nearest store call: 

1300 366 644 (Local Call Charge) 
Or Fax: (02) 9395 1155 

B3443 OBC